Late Linguistic Arrivals To Europe

Hungarian entered the Carpathian Basin at the tail end of the 9th century and Finnish and its congeners arrived in the Baltic region around the same time [Ed. some scholars, however, date it to much earlier in the 1st Millennium BCE], ultimately both from the southern Urals (hence Uralic) and Turkey, formerly populated by speakers of numerous Anatolian (ergo, IE) languages, including Lydian, Carian, and Hittite, the first IE tongue, which were overlaid by Turkic speakers from the distant east beginning in the 11th century.

From Language Log.

Note, however, that between the era in which Anatolian language were spoken in what is now Turkey, and the 11th century dominance of the Turkic language, there were also other languages spoken there, including Greek, Persian (which is moderately related to its fellow Indo-Iranian Kurdish languages, which are first attested in the 9th century but are surely at least somewhat older) and Armenian, all of which are also Indo-European languages, as well as the Semitic Arabic language, which was first spoken by significant numbers of people in Anatolia (and also in Iberia) in the 7th century.

Other languages also arose or first appeared in Europe in the Middle Ages.

The Indo-Aryan (i.e. Sanskrit derived) language(s) of the Romani people, a remote branch of the Indo-European language not previously found in Europe arrived in the 9th to 14th centuries. The Semitic influenced Germanic Yiddish language arose roughly the 9th century. The Semitic Maltese language also didn't come into being until the Middle Ages, arising roughly the 11th century.

Basque is the only remaining non-Indo-European language in Europe which was present there prior to the Middle Ages, although others, such as Etruscan, which was last attested in the 1st century, survived into the Roman era.

The Intra-African Slave Trade And Its Consequences

Contrary to some "Afro-Centric" educators, Egypt is darker skinned and has more sub-Saharan ancestry (as confirmed by modern and ancient DNA) now than it did in the classical era and in earlier times.

What happened?

A lot of sub-Saharan Africans were forced into slavery and delivered to the Middle East and North Africa (including Egypt) during the Middle Ages.

Back To Genetics Basics

For those of you who are new to this, here is a nice illustration of how different kinds of human DNA work (from DNA Explained).

Evolution In Human Pigmentation In Europe

As recently as 2500 years ago, many Europeans were a lot less white. 

The colour of eyes, hair, and skin among Eurasians and Africans is no longer a mystery. The evolution of light skin, hair, and eyes in Eurasia occurred over thousands of years, influenced by natural selection of genes and complex migration, reveals a new preprint study.

“The shift towards lighter pigmentation turned out to be slower than expected, with half of the individuals showing dark or intermediate skin colours well into the Copper and Iron Ages,” wrote the researchers in the study.

Researchers from the University of Ferrara, Italy, have used ancient DNA evidence to understand the natural colour of skin, eyes, and hair in humans from Eurasia. The study analysed DNA samples ranging from 45,000 to 1,700 years old, representing about 34 countries. . . .

[T]he first humans in Eurasia were dark-skinned and dark-haired, originating from warm climates. These darker-skinned humans had more melanin—a pigment that blocks the UV rays the body uses to produce vitamin D—compared to their lighter-skinned kin in the evolutionary cycle. Vitamin D, in turn, is crucial for bone health and strengthening the immune system, as well as aiding calcium absorption and muscle function. . . .

By the Iron Age (1200 BC to 500 BC), light-skinned people became as common as dark-skinned ones, with gene flow being the major driver of change, as noted by the researchers in the study.

The Neolithic farmers from Anatolia, present-day Turkey, “profoundly changed the genetic makeup of populations,” write the researchers, leading to a “population turnover”.

These farmers had two key advantages over the local hunter-gatherers: a stable food supply ensured by farming and animal herding, and a lighter skin tone. A lighter skin tone is better adapted to northern regions where the intensity of UV rays is low, as low melanin content in lighter skin helps produce more vitamin D. These advantages enabled the farmers’ population to grow at a faster rate than the local hunter-gatherers, causing a major shift in the appearance of Europeans.

However, the migration of Neolithic farmers was not the sole cause of the transformation of skin colour in Europe. The researchers have attributed this transformation to a localised process of migration and interbreeding of different isolated populations.

From here.

This excerpt doesn't call out a couple of other significant factors, however, and the analysis seems a bit muddled. And, like many papers in this genre, its technical analysis is strong, but its review of the literature and ability to put their own results in that context is weak.

There was massive population replacement in Europe in the Neolithic era as farmers with ancestors predominantly in Western Anatolia expanded in a southern Cardial Pottery wave and a northern LBK wave surged into Europe starting ca. 6000 BCE in the Southeast, and finishing about 4000 BCE in the Northwest and Southwest. The amount of Mesolithic European hunter-gatherer ancestry was quite modest by the time that this had run its course. So attributing light skin to Anatolian farmer ancestry is problematic. 

The closest modern proxy for Anatolian farmer ancestry is found in the people who are native to Sardinia, depicted below (from here):

Modern Anatolians have had, on average, perhaps 10% Turkic admixture due to events taking place in the Middle Ages, also experienced significant admixture from the Eastern highlands of Iran and the Caucuses during the Copper Age, and some modest Indo-European admixture with Hittite and Greek and Persian invasions from the Bronze Age to the Iron Age. So, modern Anatolians look less like the first farmers of Europe than Sardinians do.

In most Europeans, other than Sardinians and some far northern Scandinavians, this was followed by the significant demographic shift associated with the migration of light skinned, dark eyed Indo-Europeans with ancestral roots in the vicinity of modern day Ukraine to Europe, largely in the Copper Age and Bronze Age, with something close to modern admixtures in place by around the time of Bronze Age collapse in 1200 BCE, prior to the Iron Age. In some places, like the British Isles, the demographic turnover was quite rapid (maybe a century or two) and almost total.

Also, the blue eye pigment mutation that arose once, probably around 4000 BCE in far Northern Europe, probably among some of the last European hunter-gatherers (although a recent discovery suggests that it existed in very low frequencies that mutation rate analysis misses almost twice as long ago), impacted the pigmentation phenotype. As indicated by the quoted material above, they would have been quite dark skinned despite their blue eyes. This does seem to be discussed in the paper itself, even though it isn't really discussed in the article quoted above about the paper.

The modern Northern European pigmentation phenotype didn't really come together until blue eyed Northern European farmers and herders admixed with lighter skinned Indo-Europeans.

The discussion of the paper also seems to understate the importance of human evolution based upon selective fitness, which was definitely an important factor that has been documented in multiple studies of ancient DNA over time, and is ongoing. Pigmentation genes have been some of the stronger sites of selective fitness based evolution in the European gene pool.

Neanderthals would have been lighter skinned than European hunter-gatherers for the entire time that they co-existed in Europe, although light skin and light colored eyes in modern Europeans is not believed to be a product of Neanderthal admixture.

The pre-print and its abstract are as follows:

Light eyes, hair and skins probably evolved several times as Homo sapiens dispersed from Africa. In areas with lower UV radiation, light pigmentation alleles increased in frequency because of their adaptive advantage and of other contingent factors such as migration and drift. However, the tempo and mode of their spread is not known. Phenotypic inference from ancient DNA is complicated, both because these traits are polygenic, and because of low sequence depth. 

We evaluated the effects of the latter by randomly removing reads in two high-coverage ancient samples, the Paleolithic Ust’-Ishim from Russia and the Mesolithic SF12 from Sweden. We could thus compare three approaches to pigmentation inference, concluding that, for suboptimal levels of coverage (<8x), a probabilistic method estimating genotype likelihoods leads to the most robust predictions. 

We then applied that protocol to 348 ancient genomes from Eurasia, describing how skin, eye and hair color evolved over the past 45,000 years. The shift towards lighter pigmentations turned out to be all but linear in time and place, and slower than expected, with half of the individuals showing dark or intermediate skin colors well into the Copper and Iron ages. We also observed a peak of light eye pigmentation in Mesolithic times, and an accelerated change during the spread of Neolithic farmers over Western Eurasia, although localized processes of gene flow and admixture, or lack thereof, also played a significant role.

Silvia Perretti, Maria Teresa Vizzari, Patrícia Santos, Enrico Tassani, Andrea Benazzo, Silvia Ghirotto, Guido Barbujani, "Inference of human pigmentation from ancient DNA by genotype likelihood" bioRxiv (February 12, 2025) https://doi.org/10.1101/2025.01.29.635495

The results section of the paper states, in part::

Paleolithic period

(from approximately 45,000 to 13,000 years ago; 12 samples; 11 typed for eye color, hereafter E, 10 for hair color, hereafter H; 12 for skin color, hereafter S; one of them is the Ust’-Ishim test sample). 

Dark phenotypes are inferred for all traits for almost all the samples analyzed. The only exception is a Russian sample, Kostenki 14, dated to between 38,700 and 36,200 years ago, which exhibits an intermediate skin color.

Mesolithic period

(from approximately 14,000 to 4,000 years ago; 66 samples; 35 E, 63 H, 53 S; one of them is the SF12 test sample). 

Light eye colors are inferred for 11 samples; they come from Northern Europe, France and Serbia. By contrast, all 24 samples from the easternmost regions only display the dark phenotype. In Serbia both phenotypes coexist, one with blue eyes and four with brown eyes. 

61 samples show dark hair phenotypes, with the exception of 1 Swedish and 1 Serbian sample, both showing blonde features. 

Skin color displays a broader range of phenotypes: predominantly dark (43 samples), with regions in Europe also showing intermediate phenotypes (seven samples from Denmark, France, Georgia, Russia, Serbia, and Spain) and the earliest light phenotypes observed in this study (three samples from France and Sweden). 

In this time transect we observe for the first time an individual with inferred blue eyes, blonde hair, and light skin, NEO27, a hunter-gatherer from Sweden who lived approximately 12,000 years ago.

Neolithic period

(from approximately 10,000 to 4,000 years ago; 132 samples, 93 E, 120 H, 93 S). 

We still observe the majority of individuals showing the dark eye phenotype (81 samples), including France, in which we previously found only light phenotype. Both dark and light eye phenotypes are observed in Northern and Central-Eastern Europe, with the light phenotype inferred in 12 samples from Austria, Denmark, Greece, Ireland, Latvia, Serbia, and Sweden. 

Hair color is predicted as dark in almost all samples, with one exception from Austria who has an intermediate phenotype and five from Denmark, Greece, Ireland, and Serbia with light phenotype. Additionally, we observed for the first time in our dataset one sample with red hair, from Turkey. 

The skin phenotype is more variable, with regions in Europe (Portugal, Italy, Austria, Germany, Hungary, Estonia, and Russia) and Western Asia (Iran and Turkey) exhibiting exclusively a dark phenotype, whereas other regions show either both dark and intermediate phenotypes (25 samples exhibit the latter, from Croatia, Denmark, France, Greece, Ireland, Latvia, Malta, Poland, Serbia, Sweden, and Ukraine), or even light skin phenotypes (in five samples from the Czech Republic, Great Britain, Latvia, Sweden, and Ukraine).

Copper Age

(from approximately 6,000 to 3,500 years ago; 42 samples, 31 E, 33 H, 28 S). 

Even during the Copper Age dark phenotypes are prevalent. Most samples, 26, showed dark eyes, with the light phenotype present in five samples from Denmark, Hungary, Italy, and Romania.

Hair phenotypes remain mostly dark, with only one sample showing intermediate hair color (Denmark) and one samples exhibiting light hair color (Romania). 

Skin color is still predominantly dark (17 samples) in Eastern Europe, and the Iberian Peninsula, but intermediate skin tones are observed in Spain, Kazakhstan, and Central Europe (seven samples from Hungary, Italy, the Netherlands, Poland, and Romania), and light skins in Denmark, Great Britain, and Romania (four samples).

Bronze Age

(from approximately 7,000 to 3,000 years ago; 71 samples, 55 E, 64 H, 43 S). 

In this time period we observed an increasing proportion of light eye phenotype. While 39 samples throughout Europe and Asia are still exhibiting dark eyes, 16 samples display a light phenotype. These light phenotypes are still mainly found in Europe, but are also emerging in other regions such as Russia and Jordan, and as far East as Kazakhstan. 

Dark hair phenotypes remain predominant in most of Europe and Asia (49 samples), with intermediate phenotypes present in two samples from Denmark and Hungary. However, there is a greater proportion of light phenotypes (12 samples), specifically in Northern and Central-Eastern Europe, and they appear in Italy, Russia, Jordan, and Kazakhstan. One sample from Greece exhibits red hair. 

Western Europe, Southern Europe, Russia, and Southern Asia still exhibit a higher frequency of dark skin phenotypes (22 samples), but we also observed an increase in intermediate phenotypes in Central Europe and Central-Eastern Europe, as well as their first appearance in Russia (15 samples in total). The light phenotype emerged in six samples from the Czech Republic, Denmark, Estonia, France, Great Britain, and Hungary. 

During this period, we observed an increase in the co-occurrence of estimated blue eyes, blonde hair, and light skin, with four samples exhibiting this combination of phenotypes: I7198 from the Czech Republic, EKA1 from Estonia, I2445 from England, and SZ1 from Hungary.

Iron Age

(from approximately 3,000 to 1,700 years ago; 25 samples, 15 E, 19 H, 11 S). 

In this phase, the dark eye phenotype (10 samples) is present in Great Britain, Spain, and Russia, while the light eye phenotype (3 samples) is found in Denmark and Finland. Italy, and Kazakhstan exhibit both phenotypes. 

Hair remains predominantly dark throughout Europe and Asia (14 samples), with one intermediate phenotype observed in Denmark and four light phenotypes in Denmark, Finland, Italy, and Kazakhstan. 

Skin color analysis shows the dark phenotype (six samples) in Russia, Kazakhstan, and Italy. The intermediate phenotype (three samples) in Denmark, Kazakhstan, and reappears in Spain. The light phenotype (two samples) is still present in Northern Europe. 

A combination of blue eyes, blonde hair, and pale skin is observed in two samples: VK521 from Denmark and DA236 from Finland.

Cannibalism Was A Thing In Post-Glacial Hunter-Gather Poland

Just two thousand years after the Last Glacial Maximum in Europe, near the fringe of the retreating glaciers, the hunter-gathers repopulated Europe from refugia in the Caucuses, on the Italian Peninsula, and from Iberia. These people sometimes practiced cannibalism. We don't fully understand why, but their life did involve living on the brink of starvation for extended period of time. 

It could be that the taboo against cannibalism was first broken in some situation where it was dictated by dire necessity, and that once this taboo was broken, the practice morphed into something with religious significance or a way to treat troublesome rivals or enemies, that perhaps helped them deal with the guilt that arose from breaking the taboo the first time. 

Then again, human sacrifice and cannibalism were practiced in the Americas after the Neolithic revolution occurred independently there in circumstances where the threat of starvation was probably a more distant memory.

The manipulation of human corpses started to become commonplace during the Upper Paleolithic. This well-documented behavior among Magdalenian peoples consists of perimortem manipulation and the removal of soft tissues and has been understood as forming part of the cultural repertoire of mortuary actions. 

The study of these practices has given rise to several interpretations with the consumption of human flesh (cannibalism) occupying a central position. The human assemblage of Maszycka Cave (18,000 cal. BP) is part of this ongoing debate. Although initial research in the 1990s suggested cannibalism, more recent studies challenge this interpretation arguing that the low incidence of human activity rule out the likelihood of processing for the purpose of consumption and proposing skull selection as a funerary practice. 

This study reviews the assemblage and presents previously unpublished postcranial skeletal specimens along with evidence of whole-body manipulation for consumption. This behavior is also observed in other chronologically and culturally similar assemblages throughout continental Europe, suggesting that cannibalism was integral practice within the cultural systems of these Magdalenian groups.

Marginedas, F., Saladié, P., Połtowicz-Bobak, M. et al. New insights of cultural cannibalism amongst Magdalenian groups at Maszycka Cave, Poland. 15 Sci Rep 2351 (2025). https://doi.org/10.1038/s41598-025-86093-w

Agriculture Phonetically Changed Human Languages

Agriculture changes the teeth of the first farmers and that changes what they could pronounce, which changed how their languages sounded. 

The shift to processed foods following the spread of agriculture led to less wear on human teeth, altering jaw growth and making slight overbites common in adults. This anatomical change facilitated the pronunciation of labiodental sounds like “f” and “v,” which contributed to language diversification in Europe and Asia around 4,000 years ago. Linguist Balthasar Bickel, in a 2019 Science paper, linked these phonetic developments to changes like the Proto-Indo-European patēr evolving into Old English faeder about 1,500 years ago. This research suggests that cultural shifts can influence human biology in ways that affect language, an idea supported by evolutionary morphologist Noreen Von Cramon-Taubadel, who was not involved in the study.

From the Archaeologist page on Facebook discussing 

Damián E Blasi, Steven Moran, Scott R Moisik, Paul Widmer, Dan Dediu, Balthasar Bickel, "Human sound systems are shaped by post-Neolithic changes in bite configuration" 363 (6432) Science eaav3218 (March 15, 2019). 

The abstract and related prefatory material in the source article are as follows:

The first fricatives 

In 1985, the linguist Charles Hockett proposed that the use of teeth and jaws as tools in hunter-gatherer populations makes consonants produced with lower lip and upper teeth (“f” and “v” sounds) hard to produce. He thus conjectured that these sounds were a recent innovation in human language. Blasi et al. combined paleoanthropology, speech sciences, historical linguistics, and methods from evolutionary biology to provide evidence for a Neolithic global change in the sound systems of the world's languages. Spoken languages have thus been shaped by changes in the human bite configuration owing to changes in dietary and behavioral practices since the Neolithic.

Structured Abstract 

INTRODUCTION 

Human speech manifests itself in spectacular diversity, ranging from ubiquitous sounds such as “m” and “a” to the rare click consonants in some languages of southern Africa. This range is generally thought to have been fixed by biological constraints since at least the emergence of Homo sapiens. At the same time, the abundance of each sound in the languages of the world is commonly taken to depend on how easy the sound is to produce, perceive, and learn. This dependency is also regarded as fixed at the species level. 

RATIONALE 

Given this dependency, we expect that any change in the human apparatus for production, perception, or learning affects the probability—or even the range—of the sounds that languages have. Paleoanthropological evidence suggests that the production apparatus has undergone a fundamental change of just this kind since the Neolithic. Although humans generally start out with vertical and horizontal overlap in their bite configuration (overbite and overjet, respectively), masticatory exertion in the Paleolithic gave rise to an edge-to-edge bite after adolescence. Preservation of overbite and overjet began to persist long into adulthood only with the softer diets that started to become prevalent in the wake of agriculture and intensified food processing. We hypothesize that this post-Neolithic decline of edge-to-edge bite enabled the innovation and spread of a new class of speech sounds that is now present in nearly half of the world’s languages: labiodentals, produced by positioning the lower lip against the upper teeth, such as in “f” or “v.” 

RESULTS 

Biomechanical models of the speech apparatus show that labiodentals incur about 30% less muscular effort in the overbite and overjet configuration than in the edge-to-edge bite configuration. This difference is not present in similar articulations that place the upper lip, instead of the teeth, against the lower lip (as in bilabial “m,” “w,” or “p”). Our models also show that the overbite and overjet configuration reduces the incidental tooth/lip distance in bilabial articulations to 24 to 70% of their original values, inviting accidental production of labiodentals. The joint effect of a decrease in muscular effort and an increase in accidental production predicts a higher probability of labiodentals in the language of populations where overbite and overjet persist into adulthood. When the persistence of overbite and overjet in a population is approximated by the prevalence of agriculturally produced food, we find that societies described as hunter-gatherers indeed have, on average, only about one-fourth the number of labiodentals exhibited by food-producing societies, after controlling for spatial and phylogenetic correlation. When the persistence is approximated by the increase in food-processing technology over the history of one well-researched language family, Indo-European, we likewise observe a steady increase of the reconstructed probability of labiodental sounds, from a median estimate of about 3% in the proto-language (6000 to 8000 years ago) to a presence of 76% in extant languages. 

CONCLUSION 

Our findings reveal that the transition from prehistoric foragers to contemporary societies has had an impact on the human speech apparatus, and therefore on our species’ main mode of communication and social differentiation: spoken language.

Which Planets Are Hot, Which Planets Are Cold?

Back to basics with this cute little visual (the Sun is about 10,000º F, and about 5,600º C).

Birds Down Under

One of the earliest ever bird fossils has been found in Antarctica.

Fossils representing Cretaceous lineages of crown clade birds (Aves) are exceptionally rare but are crucial to elucidating major ecological shifts across early avian divergences. Among the earliest known putative crown birds is Vegavis iaai, a foot-propelled diver from the latest Cretaceous (69.2–68.4 million years ago) of Antarctica with controversial phylogenetic affinities. Initially recovered by phylogenetic analyses as a stem anatid (ducks and closely related species), Vegavis has since been recovered as a stem member of Anseriformes (waterfowl), or outside Aves altogether. 

Here we report a new, nearly complete skull of Vegavis that provides new insight into its feeding ecology and exhibits morphologies that support placement among waterfowl within crown-group birds. Vegavis has an avian beak (absence of teeth and reduced maxilla) and brain shape (hyperinflated cerebrum and ventrally shifted optic lobes). The temporal fossa is well excavated and expansive, indicating that this bird had hypertrophied jaw musculature. The beak is narrow and pointed, and the mandible lacks retroarticular processes. Together, these features comprise a feeding apparatus unlike that of any other known anseriform but like that of other extant birds that capture prey underwater (for example, grebes and loons). The Cretaceous occurrence of Vegavis, with a feeding ecology unique among known Galloanserae (waterfowl and landfowl), is further indication that the earliest anseriform divergences were marked by evolutionary experiments unrepresented in the extant diversity.

Christopher R. Torres, et al., "Cretaceous Antarctic bird skull elucidates early avian ecological diversity." 638(8049) Nature 146 (2025) DOI: 10.1038/s41586-024-08390-0

Hat tip to Science Daily which provides additional explanation in a somewhat less jargon heavy way. It begins by stating:

Sixty-six million years ago, at the end of the Cretaceous Period, an asteroid impact near the Yucatán Peninsula of Mexico triggered the extinction of all known non-bird dinosaurs. But for the early ancestors of today's waterfowl, surviving that mass extinction event was like…water off a duck's back. Location matters, as Antarctica may have served as a refuge, protected by its distance from the turmoil taking place elsewhere on the planet. Fossil evidence suggests a temperate climate with lush vegetation, possibly serving as an incubator for the earliest members of the group that now includes ducks and geese.

Evidence For Non-Newtonian Gravity In Wide Binaries

A new paper shows statistically significant tensions between the assumption of Newtonian gravity (to which General Relativity conventionally applied reduces in the weak field regime) in the MOND transition region (which is not found in the non-MONDian field strength area) in an analysis of the Gaia DR3 dataset. 

The significance of the deviation is still below the five sigma discovery level (2.1 sigma in the MOND regime and 4.2 sigma for the weaker effect in the MOND transition regime), the expected value under a MOND hypothesis in the MOND transition region isn't entirely clear, and there are multiple potential sources of unmeasured systemic error (most importantly, the possibility that some data points that look like binary stars actually have three or more stars in the system with the smallest star going undetected). 

But, while it is not the definitive evidence, it is consistent with a MOND hypothesis, and it is still significant positive evidence of MONDian-like behavior in wide binary stars. This, at a minimum, justifies further investigation of, and research regarding, this hypothesis. 

(I've used a screenshot of the abstract rather than cutting and pasting it, in order to preserve the extensive formatting there.)

Kyu-Hyun Chae, "Low-Acceleration Gravitational Anomaly from Bayesian 3D Modeling of Wide Binary Orbits: Methodology and Results with Gaia DR3" arXiv:2502.09373 (February 13, 2025).

Satellite Galaxies

The number of satellite galaxies connected to the Milky Way and to the Andromeda galaxy respectively, are comparable in number to the number of planets, dwarf planets, moons, and large asteroids in the solar system.

Sadly, the preprint does not have an indexed table listing all of them and their properties, although it does analyze the properties of these satellite galaxies from a variety of perspectives. But, Wikipedia does have a list of satellite galaxies for the Milky Way, and for the Andromeda galaxy.

At the time of writing, there are 88 confirmed satellite galaxies in the LG [i.e the Local Group] (49 in the MW [i.e. the Milky Way galaxy] and 39 in M31 [i.e. the Andromeda galaxy]) and a further 15 candidate galaxies (14 in the MW and 1 in M31).

From Amandine Doliva-Dolinsky, Michelle L. M. Collins, Nicolas F. Martin, "The satellite galaxies of the Milky Way and Andromeda" arXiv:2502.06948 (February 10, 2025) (to be published as a chapter in the forthcoming Encyclopedia of Astrophysics).

The abstract of the pre-print states:

The satellite galaxies of the Local Group provide us with an important probe of galaxy formation, evolution, and cosmology. The two large spirals that dominate this group -- the Milky Way and Andromeda -- are each host to tens of satellites, ranging in stellar mass from M∗=3×109M⊙ down to as little as M∗∼1000M⊙. In this review, we (1) provide an overview of the known satellite population of the Milky Way and Andromeda, including how they are discovered and their observed properties; (2) discuss their importance in understanding the nature of dark matter, star formation in the early Universe, the assembly histories of their massive hosts, and the impact of reionisation on the lowest mass galaxies; and (3) highlight the coming revolution and challenges of this field as new observatories and facilities come online. In the coming decades, the study of Local Group satellites should allow us to place competitive constraints on both dark matter and galaxy evolution.

Indo-European Genetic Origins

I'm still not convinced that they are analyzing the data in a way the correctly interprets what is going on with the Anatolians. To be clear, I'm not disputing their genetic data, only the narrative that they've employed to explain it.

The Yamnaya archaeological complex appeared around 3300 bc across the steppes north of the Black and Caspian Seas, and by 3000 bc it reached its maximal extent, ranging from Hungary in the west to Kazakhstan in the east. To localize Yamnaya origins among the preceding Eneolithic people, we assembled ancient DNA from 435 individuals, demonstrating three genetic clines. 

A Caucasus–lower Volga (CLV) cline suffused with Caucasus hunter-gatherer ancestry extended between a Caucasus Neolithic southern end and a northern end at Berezhnovka along the lower Volga river. Bidirectional gene flow created intermediate populations, such as the north Caucasus Maikop people, and those at Remontnoye on the steppe. 

The Volga cline was formed as CLV people mixed with upriver populations of Eastern hunter-gatherer ancestry, creating hypervariable groups, including one at Khvalynsk. 

The Dnipro cline was formed when CLV people moved west, mixing with people with Ukraine Neolithic hunter-gatherer ancestry along the Dnipro and Don rivers to establish Serednii Stih groups, from whom Yamnaya ancestors formed around 4000 bc and grew rapidly after 3750–3350 bc. 

The CLV people contributed around four-fifths of the ancestry of the Yamnaya and, entering Anatolia, probably from the east, at least one-tenth of the ancestry of Bronze Age central Anatolians, who spoke Hittite. We therefore propose that the final unity of the speakers of ‘proto-Indo-Anatolian’, the language ancestral to both Anatolian and Indo-European people, occurred in CLV people some time between 4400 bc and 4000 bc.

Iosif Lazaridis, et al, "The genetic origin of the Indo-Europeans" Nature (February 5, 2025).

Note that I blogged the pre-print of this paper in April of 2024. I haven't determined yet what, if anything, has changed since the pre-print.

Q-Balls As Dark Matter?

A new preprint, entitled "Can Q-balls describe cosmological and galactic dark matter?" by Susobhan Mandal and S. Shankaranarayanan proposes "Q-Balls" as a dark matter candidate (hat tip to neo). The abstract and introduction to the preprint, excerpts of which explains the hypothesis (but contradict each other on the question of Q-ball mass, a probably that may be fixed in edits to the pre-print). I have interlineated my commentary in square brackets.

Abstract 

Q-balls, which are localized, non-topological solitons, can be a bridge between the two hypotheses. Q-balls formed in the early Universe can mimic CDM at cosmological scales. Interestingly, Q-balls can exhibit MOND-like behavior in the late Universe at galactic scales, providing a unified framework. Specifically, we demonstrate that millicharged composite Q-balls formed from complex scalar fields, decoupled from the background radiation, can naturally arise during the radiation-dominated epoch. From the matter-radiation equality, we also obtain the mass of Q-balls to be 1 eV [Ed. the body text says 41 eV], which are much smaller than the electron mass. Using the constraints from the invisible decay mode of ortho-positronium, we obtain Q<3.4×10^−5. We also establish an upper bound on the number density of Q-balls, which depends on the charge of the Q-ball and the small initial charge asymmetry. . . .  

Introduction 

The most convincing evidence for dark matter (DM) is found at the cosmological scales. The Λ-Cold-Dark-Matter (ΛCDM) model, in which DM is composed of collisionless particles, fits the temperature fluctuations of the Cosmic Microwave Background (CMB), the matter power spectra, and the abundance and mass function of galaxy clusters extraordinarily well. The foundation of the conventional cold dark matter hypothesis is the existence of non-relativistic, collision-free dark matter particles. Also, dark matter constituents cannot possess an electric charge comparable to that of electrons unless they are extremely heavy. 

However, this does not rule out the intriguing possibility of electrically millicharged particles. Millicharged particles have an electric charge e′ = εe, where e is the electron charge and ε ≪ 1. These particles can be either bosons or fermions, and they naturally arise in a wide range of models. [Ed. the exquisite sensitivity of physics measurements to even slight electromagnetic charges makes an EM millicharged particle hypothesis highly unlikely. For example, this would impact muon g-2 measurements in ways that are not observed and are at parts per billion levels.]

This naturally raises the question: Is there a framework where the DM behaves as a CDM in the cosmological scales and can mimic MOND in the galaxy scales? In other words, is there a mechanism where CDM and MOND share a common ancestry?  

This work proposes an alternative mechanism with the same origin but behaves differently in the cosmological and galactic scales. We demonstrate that non-topological solitons — the Q-balls — can be formed in the early Universe and mimic CDM at the cosmological scales. Specifically, we show that Q-balls from complex scalar field decoupled from the background radiation can naturally form in the radiation-dominated epoch. In contrast, they mimic MONDat galactic scales in the late Universe. 

Q-balls can naturally form in a wide range of particle physics models and can be produced in the early Universe, and can be stable. Recently, the existence of Q-balls in the dark sector of the Universe and its astrophysical consequences have gained interest. [Ed. actually, Q-ball models are far out of the mainstream in particle physics, involve Byzantine contortions to produce a questionable physics model disfavored by Occam's Razor, and aren't well-motivated.]

For a class of complex scalar field theory, we show that Q-ball configurations exist in the recombination epoch during the radiation-dominated (RD) era in the early Universe. We show that the Q-balls formed satisfy the two conditions — stability and existence. We show that the density perturbations that reenter during the recombination epoch increase the production of Q-balls and compute the number density of the thin-wall Q-balls in the Universe. We also compute the upper bound on the number density of Q-balls based on its global U(1) charge and small primeval charge asymmetry, which might be created due to primordial anomaly due to helical magnetic fields. It is also possible to generate charge asymmetry due to the helicity of the gravitational waves. From the matter-radiation equality, we also obtain the mass of Q-balls to be 41 eV, which are much smaller than the electron mass. Combined with the invisible decay mode of ortho-positronium leads to Q < 3.4×10^−5. Suggesting that the millicharged Q-balls are DM candidates responsible for the early structure. 

Since the Q-balls decay as 1/a3(η) in the early epoch, they behave like CDM in the cosmological scales. Later, we look at the possibility of forming Bose-Einstein condensate (BEC) and superf luidity by these Q-balls in the present Universe (dominated by dark energy). 

We find the Q-balls can indeed form these phases of matter, which eventually lead to the law predicted by Modified Newtonian dynamics at the galactic scale. Thus, we show that the cosmological and galactic dark matter share a common ancestry, representing distinct phases of a single background fluid. 

The possibility that galactic DM can be a superfluid has recently attracted attention. This is based on two key ideas: The first notion that the DM forms a superfluid within galaxies with a coherence length equal to the size of the galaxies is widespread. Second, the DM superfluidity phenomenon occurs frequently if the DM particle is sufficiently light and has a significant self-interaction. A superfluid is a state of matter where impurity particles flow without dissipation as long as they remain below a critical velocity, a phenomenon known as Landau’s criterion. Superfluidity and Bose-Einstein condensation are intimately related phenomena. In order to acquire a superfluid phase, BoseEinstein condensation must first occur; however, the converse is not true, as the superfluidity property disappears in the absence of interactions. Thus, we show that Q-balls can be considered a DM candidate, which acts as a composite object at the cosmological scale and behaves as collective excitation on the galactic scale.

The background analysis of why other solutions to explaining dark matter phenomena don't work in the introduction is also interesting, although not very rigorous: 

On cosmological scales, CDM accurately predicts the formation of structure. At smaller distance scales, however, the accurate picture is nebulous. As galaxy simulations and measurements have advanced, the CDM paradigm has encountered several challenges. Contradictory predictions concerning structure on galactic and sub-galactic scales, however, seem to result from it. Local group dwarf satellite galaxies present the main obstacles. Dwarf satellites are excellent candidates for in-depth studies of DM microphysics due to their DM dominance. With the discovery of ultra-faint dwarfs, the old ”missing satellite” problem has been gradually resolved, and other, more pressing problems have emerged. Recent attempts to match populations of simulated subhaloes and observed Milky Way (MW) dwarf galaxies uncovered a “too big to fail” issue. The most massive black halos are too dense to contain the brightest MW satellites. Even more perplexing is that most MW and Andromeda (M31) satellites co-rotate within immense planar structures. This can not be explained within the ΛCDM model. Also, recently, it has been suggested that the growth rate of perturbations is higher than predicted by the ΛCDM model. These issues raise the possibility or implication that dark matter is not cold or collision free. 

Weakly interacting massive particles (WIMPS) or axions, the two generally accepted possibilities for dark matter, would be excluded in that case. 

The defining feature of the thermal WIMP is its relic abundance naturally explained by the freeze-out process with a weak-scale cross-section. This cross-section would account for the elusive non-gravitational interactions of dark matter (DM). WIMP candidates naturally appear around the weak scale in many theories beyond the standard model (BSM). While a simple thermal WIMP is not the only possibility for DM, it is a compelling scenario that demands definitive testing. If WIMPs constitute the DM in the Universe, including our Galaxy’s DM halo, they should be ubiquitous, even in our immediate vicinity. This raises the question of directly detecting these WIMPs in the laboratory. This possibility was first explored by M Goodman and E Witten in 1985. They proposed that WIMPs elastically scattering off nuclei of chosen detector materials might leave recoiling nuclei with detectable kinetic energies. Goodman and Witten suggested that coherent elastic scattering of WIMPs off nuclei, with the cross-section proportional to A (A is the mass number of the nucleus), could yield a detectable rate of scattering events. Subsequently, numerous experiments worldwide, employing diverse detection techniques and materials, have sought WIMPs. However, to date, none of these experiments have definitively claimed WIMP detection. 

In contrast, Modified Newtonian Dynamics (MOND) provides a radical alternative to DM by modifying the Newtonian force law. According to MOND, the modification to Newtonian force law occurs at low acceleration. Thus, MOND can be understood as either a change to the Poisson equation that modifies gravity or a shift in inertia that modifies inertia by breaking the inertial and gravitational mass equivalence. This empirical force law has astonishingly explained a broad range of galactic events. It predicts asymptotically flat rotation curves for spiral galaxies and provides an excellent fit to exact rotation curves. The only free parameter is the critical acceleration a(0), whose best-fit value is the Hubble constant. Interestingly, the Baryonic Tully Fisher Relation (BTFR) is a direct result of this force law deep within the MOND regime. In ΛCDM, galaxies are surrounded by extensive DM halos, so a merger cannot be avoided. In contrast, in MOND, there is only stellar dynamical friction so that a merger can be avoided. According to MOND, tidal dwarf galaxies should have flat rotation curves and reside on the BTFR, consistent with NGC5291’s dwarfs. On extragalactic scales, however, MOND faces more severe problems. 

MOND and CDM are, therefore, effective in almost mutually exclusive regimes. The Λ-CDM model can explain the expansion and linear growth histories and the abundance of clusters, but on a galactic scale, it has certain limitations. MOND explains the observable features of galaxies reasonably well in general, notably the empirical scaling relations. However, it is highly improbable that it can be consistent with the complex shape of the CMB and matter power spectra. [Ed. this speculation is false.] 

To our knowledge, it is difficult to have CDM and MOND behaviors through particle dark matter models. As mentioned earlier, WIMPS or Axions cannot connect these theories in their respective mutually exclusive domains. More than that, WIMPs and axions cannot explain the low energy theory of phonon modes at the galactic scale as their rest mass energy is very high. [Ed. WIMPS are indeed largely ruled out. This paper has no solid support for the claims it makes about axion-like particle dark matter, which relies on mechanism similar to Q-balls to come closer to reproducing MOND than CDM does.]

Recently, the interest in Primordial Blackholes (PBHs) as a dark matter candidate over particle dark matter candidates is to fill this gap. Also, PBHs are not subject to the Big Bang nucleosynthesis (BBN) constraints of Baryons, making them non-baryonic entities that exhibit similar characteristics to CDM particles. [Ed. the paper fails to note that PBH is largely ruled out as the primary source of DM, but dismisses this hypothesis anyway without explanation. "For reasonable assumptions on those PBH binaries' properties before their evolution inside dark matter halos, we get that fraction to be in the range of 5×10^−3 to 0.1, for PBH masses of 5-80M⊙." Of course, the linked paper itself has issues, because PBH's are largely ruled out for masses other than asteroid masses, by micro-lensing for larger PBH's and by evaporation via Hawking radiation for smaller ones. There is also strong suggestive evidence from other sources that asteroid sized PBH's don't exist. PBH's of 5-80⊙ aren't what the DM candidate PBH's are talking about.]

Tentative DM Signal Not Replicated

The DAMA/LIBRA modulation signal is proposed to be a signal of dark matter annihilation. But, the ANAIS-112 experiment has failed to replicate this signal, casting doubt upon it as evidence of dark matter.

This article presents the results of the annual modulation analysis corresponding to six years of ANAIS-112 data. Our results, the most sensitive to date with the same target material, NaI(Tl), are incompatible with the DAMA/LIBRA modulation signal at a 4σ confidence level. Such a discrepancy strongly challenges the DAMA/LIBRA dark matter interpretation and highlights the need to address systematic uncertainties affecting the comparison, particularly those related to the response of detectors to nuclear recoils, which may require further characterization of the DAMA crystals.

From here.

Constraints On Ultra-High Energy New Physics From Cosmic Rays

Deligny cleverly uses ulta-high energy cosmic rays as a natural experiment to discern limits on possible new high energy physics beyond the Standard Model of Particle Physics (BSM) at energies well beyond those that can be explored in existing, and even next generation, particle colliders.

Various phenomena of physics beyond that of the Standard Model could occur at high scale. Ultra-high energy cosmic rays are the only particles available to explore scales above a few dozens of TeV. Although these explorations are much more limited than those carried out with colliders, they provide a series of constraints in several topics such as tests of Lorentz invariance, dark matter, phase transitions in the early universe or sterile neutrinos. Several of these constraints are reviewed in these proceedings of UHECR2024 based on searches for anomalous characteristics in extensive air showers or searches for ultra-high energy gamma rays and neutrinos.

O. Deligny, "Various constraints on BSM physics from extensive air showers and from ultra-high energy gamma-ray and neutrino searches" arXiv:2501.19322 (January 31, 2025).

The body text discusses the following constraints, most of which are rather obscure:

1. Lorentz Violation.

If Lorentz violation (i.e. deviations from special relativity) exists, a certain parameter the suppresses neutral pion decay would be negative, which would also allow individual photons to decay without interacting with other particles. This parameter is observationally constrained by be not smaller than negative 6 parts per 10^21.

In general, the observational constraints on Lorentz violation from this source, as well as from other methodologies, are extremely strict, but can't entirely rule out extremely slight Lorentz violations.

2.  Superheavy dark matter particles

Constraints on superheavy dark matter particles including "inflatons" and spin 3/2 gravitinos can be established:

Other observational astronomy constraints not mentioned also disfavor ultra-heavy dark matter particle candidates, even in the parts of the parameters space where cosmic ray observations alone allow them.

3. Early Universe Phase Transitions

Cosmic strings "are regions of space-time that remain in a symmetry unbroken phase due to boundary conditions that topologically restrict their decay." These would spontaneously decay in the very early universe resulting in a phase transition as the U(1) symmetry and force that holds these strings together completely disappears as the universe cools decaying into still very high energy beyond the Standard Model particles that decay into Standard Model particles.

The energies at which such a phase transition could occur are constrained by ultra-high energy cosmic ray observations.

4. Anomalous Ultra-High Energy Sterile Neutrinos

The body text notes that:

In the SM, the neutrino-nucleon scattering cross-section increases with the energy of the incoming neutrino. Consequently, ultra-high-energy neutrinos may only propagate through the Earth for relatively short distances of the order of O(100) km.

Since the path through Earth to upwards to a neutrino detector is more than 100 km for all but the most grazing angles of approach relative to the surface of the Earth, ultra-high energy neutrinos aren't expected from that direction. But "two “anomalous” radio pulses [have been] observed with the ANITA instrument compatible with EASs developing in the upward direction and inconsistent with SM expectations[.]" 

Efforts have been made to devise SM and BSM explanations for these two outlier data points. An explanation of these anomalies with BSM neutrino physics that could both produce these anomalies, and not produce significantly more anomalies than were observed by ANITA, however, is quite constrained.

One of the less radical BSM neutrino physics possibilities is a sterile neutrino the evades interaction with nucleons in the Earth because it has no weak force interactions until it oscillates into an active high energy neutrino shortly before it reaches the detector. The allowed parameter space of such a sterile neutrino in terms of the oscillation probability U to a sterile neutrino, and the sterile neutrino mass has been established subject to certain assumptions and is shown in the chart below. This mostly limit a sterile neutrino explanation to sterile neutrinos with more than 4 GeV in mass but less than 16 GeV in mass (compared to significantly less than 1 eV for the most massive active neutrino mass, which is ten orders of magnitude smaller), and a probability of transitioning to from sterile neutrino to an active neutrino that is probably in the range of 10^-5 to 10^-6. These parameters are far outside the range that has been suggested by weak anomalies in other searches for sterile neutrinos (which are themselves mutually inconsistent with each other).

Less frequent transition probabilities for a heavy sterile neutrino are discouraged by a lack of close enough sources to produce two ultra-high energy sterile neutrino events, while laboratory based sterile neutrino searches rule out more frequent transition probabilities.

These transition probabilities are four to six orders of magnitude smaller than any of the PMNS matrix neutrino oscillation probabilities, and are two to four orders of magnitude smaller than the smallest CKM matrix probabilities of W boson mediated transitions between first and third generation quark flavors (which differ in mass by five orders of magnitude). Sterile neutrinos of less than 4 GeV masses are also disfavored as an explanation.

This is the only experimental data suggestive of sterile neutrinos with these parameters.

Ancient Demographic Change In China

A new review paper sums up the demographic history of China from hunter-gatherers who were there before the Last Glacial Maximum (ca. 20,000 years ago) to the modern era, using recent ancient DNA discoveries and other data. Unfortunately, it appears to be a closed access paper, so I can't glean much from it beyond the abstract.

Over the past decade, the continuous development of ancient genomic technology and research has significantly advanced our understanding of human history. Since 2017, large-scale studies of ancient human genomes in East Asia, particularly in China, have emerged, resulting in a wealth of ancient genomic data from various time periods and locations, which has provided new insights into the genetic history of East Asian populations over tens of thousands of years. Especially since 2022, there emerged a series of new research progresses in the genetic histories of the northern and southern Chinese populations within the past 10,000 years. However, there is currently no systematic review focused on these recent ancient genomic studies in East Asia. Therefore, this article emphasizes the study of ancient human genomes in China and systematically reviews the genetic patterns and migration history of populations in East Asia since the Late Paleolithic.  

Existing research indicates that by at least 19,000 years ago, there was a north-south differentiation among ancient East Asian populations, leading to different genetic lineages divided by the Qinling-Huaihe line. Gene flow and interactions between northern and southern East Asians began in the Early Neolithic and were further strengthened from the Mid-Neolithic. By the historical period, northern East Asian ancestry played a profound role in the genetic components of southern populations, shaping the genetic structure of present-day Chinese populations. 

Throughout this process, ancient populations in northern and southern China also engaged in extensive interactions through coastal and inland routes with populations from surrounding regions, including Siberia, Japan, Korea, Southeast Asia, and Pacific islands, playing a crucial role in the formation of different linguistic groups. These studies have charted the evolutionary and interaction history of East Asian populations over tens of thousands of years; yet, many unresolved mysteries remain. Further exploration is needed through ancient genomic data from additional time periods and broader geographic areas to facilitate a more comprehensive and detailed investigation, thereby advancing related scientific questions.

Ping WJ, Xue JY, Fu QM. "Ancient DNA elucidates the migration and evolutionary history of northern and southern populations in East Asia." 47(1) Yi Chuan.18-33. (January 2025) doi: 10.16288/j.yczz.24-224.

Matriarchal Celts

A new study published in Nature, examining ancient DNA evidence from Iron Age Celtic cemeteries in Southern England, demonstrate that these Celts, at least, were matrilocal. 

It also demonstrates the demic diffusion of Celts from continental Europe to Southern England, displacing Bronze Age Bell Beaker derived populations that were predominant in the rest of England in the first millennium before the common era. 

The paper's abstract says:

Roman writers found the relative empowerment of Celtic women remarkable. In southern Britain, the Late Iron Age Durotriges tribe often buried women with substantial grave goods. 

Here we analyse 57 ancient genomes from Durotrigian burial sites and find an extended kin group centred around a single maternal lineage, with unrelated (presumably inward migrating) burials being predominantly male. Such a matrilocal pattern is undescribed in European prehistory, but when we compare mitochondrial haplotype variation among European archaeological sites spanning six millennia, British Iron Age cemeteries stand out as having marked reductions in diversity driven by the presence of dominant matrilines. 

Patterns of haplotype sharing reveal that British Iron Age populations form fine-grained geographical clusters with southern links extending across the channel to the continent. Indeed, whereas most of Britain shows majority genomic continuity from the Early Bronze Age to the Iron Age, this is markedly reduced in a southern coastal core region with persistent cross-channel cultural exchange. This southern core has evidence of population influx in the Middle Bronze Age but also during the Iron Age. This is asynchronous with the rest of the island and points towards a staged, geographically granular absorption of continental influence, possibly including the acquisition of Celtic languages.

Ethnic Segregation In 8th Century Austria

The Avars from Asia Steppes and European farmers co-existed in segregated communities in the early Middle Ages in Austria for at least six generations.

Researchers carried out an archeogenetic study of human remains from more than 700 individuals from the Early Middle Ages. Two large burial sites, Modling and Leobersdorf, have been genetically analyzed in their entirety. The surprising result was that the individuals from Leobersdorf were mostly of East Asian origin, while those buried in Modling mostly had European ancestry. Both communities lived next to each other for at least six generations. . . . 

[The result] emerged from a genetic study of burial grounds from the Avar period in the 8th century CE. The Avars had arrived in the 6th century from the East Asian Steppes and settled in East Central Europe among a mixed population.

From Science Direct. The article quoted above is based upon the academic paper whose abstract and citation are provided below:

After a long-distance migration, Avars with Eastern Asian ancestry arrived in Eastern Central Europe in 567 to 568 CE and encountered groups with very different European ancestry. 

We used ancient genome-wide data of 722 individuals and fine-grained interdisciplinary analysis of large seventh- to eighth-century ce neighbouring cemeteries south of Vienna (Austria) to address the centuries-long impact of this encounter. We found that even 200 years after immigration, the ancestry at one site (Leobersdorf) remained dominantly East Asian-like, whereas the other site (Mödling) shows local, European-like ancestry. These two nearby sites show little biological relatedness, despite sharing a distinctive late-Avar culture. 

We reconstructed six-generation pedigrees at both sites including up to 450 closely related individuals, allowing per-generation demographic profiling of the communities. Despite different ancestry, these pedigrees together with large networks of distant relatedness show absence of consanguinity, patrilineal pattern with female exogamy, multiple reproductive partnerships (for example, levirate) and direct correlation of biological connectivity with archaeological markers of social status. The generation-long genetic barrier was maintained by systematically choosing partners with similar ancestry from other sites in the Avar realm. Leobersdorf had more biological connections with the Avar heartlands than with Mödling, which is instead linked to another site from the Vienna Basin with European-like ancestry. Mobility between sites was mostly due to female exogamy pointing to different marriage networks as the main driver of the maintenance of the genetic barrier.

Ke Wang, et al., "Ancient DNA reveals reproductive barrier despite shared Avar-period culture." Nature (January 15, 2025) DOI: 10.1038/s41586-024-08418-5 (open access).

Garbage Experiment Of The Day

This experiment is searching for dark matter that must have properties in a part of the dark matter parameter space that direct dark matter detection experiments and particle collider tests have already ruled out by a dozen orders of magnitude or more. It is also basically ruled out by the LAT collaboration.

It is arguably one of the biggest wastes of time in the astronomy community right now. I would never have voted to fund it, if I were sitting on a committee considering the proposal.

Numerous observations confirm the existence of dark matter (DM) at astrophysical and cosmological scales. Theory and simulations of galaxy formation predict that DM should cluster on small scales in bound structures called sub-halos or DM clumps. While the most massive DM sub-halos host baryonic matter, less massive, unpopulated sub-halos could be abundant in the Milky Way (MW), as well and yield high-energy gamma rays as final products of DM annihilation. Recently, it has been highlighted that the brightest halos should also have a sizeable extension in the sky. In this study, we examine the prospects offered by the Cherenkov Telescope Array Observatory (CTAO), a next-generation gamma-ray instrument, for detecting and characterizing such objects. Previous studies have primarily focused on high-latitude observations; here, we assess the potential impact of the CTAO's Galactic Plane Survey, which will provide unprecedentedly deep survey data for the inner five degrees of the Galactic plane. Our modeling accounts for tidal effects on the sub-halo population, examining the conditions under which DM sub-halos can be detected and distinguished from conventional astrophysical sources. We find that regions a few degrees above or below the Galactic plane offer the highest likelihood for DM sub-halo detection. For an individual sub-halo -- the brightest from among various realizations of the MW subhalo population -- we find that detection at the 5σ level is achievable for an annihilation cross section of ⟨σv⟩∼3×10^−25 cm^3/s for TeV-scale DM annihilating into bb¯. For a full population study, depending on the distribution and luminosity model of Galactic sub-halos, yet unconstrained cross sections in the range ⟨σv⟩∼10^−23−10^−22 cm^3/s for TeV DM candidates are necessary for the brightest sub-halos to be detected.

Christopher Eckner, et al., "Detecting dark matter sub-halos in the Galactic plane with the Cherenkov Telescope Array Observatory" arXiv:2501.09789 (January 16, 2025).

Australopithecus Was Predominantly Vegetarian

On the path of evolution from chimpanzees and bonobos on one hand, and the genus Homo on the other, in between is Australopithecus, about 3.5 million years ago. Analysis of tooth enamel from Australopithecus remains in South Africa shows that this human ancestor ate very little meat and relied predominantly on plant based food. 

The underlying paper is: Tina Lüdecke, Jennifer N. Leichliter, Dominic Stratford, Daniel M. Sigman, Hubert Vonhof, Gerald H. Haug, Marion K. Bamford, Alfredo Martínez-García. "Australopithecus at Sterkfontein did not consume substantial mammalian meat." 387 (6731) Science 309 (January 2025). DOI: 10.1126/science.adq7315

Austronesian-Papuan People Replaced The First Modern Humans In Wallacea

Wallacea is the ecological region between the Wallace Line and the Lydekker Line (image via Wikipedia at the link). The plants and animals there differ greatly from those to the west (which were connected by land to mainland Asia when sea levels were lower) because neither animals nor 46,000 years of settlers after the first modern humans to cross into it, could cross the roughly 30 miles of deep sea between the regions.

The most basal modern human populations outside Africa, which also have the greatest Denisovan admixture, are the indigenous people of Papua New Guinea and Australia. People from this wave were also present on the islands of the Wallacean Archipelago in Indonesia and lived there undisturbed for about 46,000 years. 

But, when Papuans made contact with and fused with Austronesian sea farers (who originated on the island that is now called Taiwan) around 3500 years ago, contemporaneously with the late Bronze Age in Europe, the resulting fused population replaced the descendants of the first wave of modern humans in the Wallacean Achipelago.

Significance

We present a comprehensive study of the human genetic history of the Wallacean Archipelago and West Papuan regions of Indonesia, including 254 newly sequenced genomes, mostly from previously undocumented populations. In combination with linguistic and archaeological evidence, we show that Wallacean societies were transformed by the spread of genes and languages from West Papua in the past 3,500 y—the same period that Austronesian seafarers were actively mixing with Wallacean and Papuan groups. These migrant groups have largely replaced local Wallacean ancestry sources, challenging common assumptions that Papuan-related ancestry in Wallacea descends from first human migrants enroute to Sahul >50,000 y ago, and suggesting that these ancient movements may not be readily recoverable from modern genetic data alone.

Abstract

The tropical archipelago of Wallacea was first settled by anatomically modern humans (AMH) by 50 thousand years ago (kya), with descendent populations thought to have remained genetically isolated prior to the arrival of Austronesian seafarers around 3.5 kya. 

Modern Wallaceans exhibit a longitudinal countergradient of Papuan- and Asian-related ancestries widely considered as evidence for mixing between local populations and Austronesian seafarers, though converging multidisciplinary evidence suggests that the Papuan-related component instead comes primarily from back-migrations from New Guinea. 

Here, we reconstruct Wallacean population genetic history using more than 250 newly reported genomes from 12 Wallacean and three West Papuan populations and confirm that the vast majority of Papuan-related ancestry in Wallacea (~75 to 100%) comes from prehistoric migrations originating in New Guinea and only a minor fraction is attributable to the founding AMH settlers. 

Mixing between Papuan and local Wallacean lineages appears to have been confined to the western and central parts of the archipelago and likely occurred contemporaneously with the widespread introduction of genes from Austronesian seafarers—which now comprise between ~40 and 85% of modern Wallacean ancestry—though dating historical admixture events remains challenging due to mixing continuing into the Historical Period. In conjunction with archaeological and linguistic records, our findings point to a dynamic Wallacean population history that was profoundly reshaped by the spread of Papuan genes, languages, and culture in the past 3,500 y.

Gludhug A. Purnomo , Shimona Kealy, Sue O’Connor, Raymond Tobler, et al., "The genetic origins and impacts of historical Papuan migrations into Wallacea" 121 (52) PNAS e2412355121 (December 17, 2024). Hat tip to DDeden.