Perhaps the Chinese government is not covering up the number of Covid-19 cases?
A big debate on the internet is whether China is covering up the number of cases of Covid-19 in Hubei, and more specifically Wuhan. Right now JHU says that China has 82,000 confirmed cases, as opposed to 300,000 in the USA. Both are underestimates, but there are those who believe that the Chinese death toll […]
This is a trial run (I hope!)
Early Pleistocene enamel proteome sequences from Dmanisi resolve Stephanorhinus phylogeny: Ancient DNA (aDNA) sequencing has enabled unprecedented reconstruction of speciation, migration, and admixture events for extinct taxa. Outside the permafrost, however, irreversible aDNA post-mortem degradation has so far limited aDNA recovery within the ~0.5 million years (Ma) time range. Tandem mass spectrometry (MS)-based collagen type […]
General laws of macroevolution from phylogenetics
I’ve been following the Evolution 2018 Meeting in Montpelier on Twitter. A lot of the stuff is interesting, though over my head. In biology, I began with a fascination with natural history. What we might term macroevolution today. I was that kid carrying out The Dinosaur Heresies when I was nine. But aside from the […]
Carving nature at its joints more realistically
If you are working on phylogenetic questions on a coarse evolutionary scale (that is, “macroevolutionary,” though I know some evolutionary geneticists will shoot me the evil eye for using that word) generating a tree of relationships is quite informative and relatively straightforward, since it has a comprehensible mapping onto to what really occurred in nature. […]
Unveiling the genealogical lattice
To understand nature in all its complexity we have to cut down the riotous variety down to size. For ease of comprehension we formalize with math, verbalize with analogies, and visualize with representations. These approximations of reality are not reality, but when we look through the glass darkly they give us filaments of essential insight. […]
Most mtDNA lineages expanded before the Neolithic?
A new short communication in Scientific Reports suggests that most demographic expansion as ascertained using mtDNA occurred before the Neolithic. MtDNA analysis of global populations support that major population expansions began before Neolithic Time…
The end of phylogenetic controversies
I put up kind of a ridiculous title. But I do hope that at some point in the near future we’ll have some of the same flavor of debates on the macroevolutionary time scale that we have on the human microevolutionary time scale. There’ll be a…
On phylogenetic instrumentalism
ADMIXTURE and STRUCTURE tests aren’t formal mixture tests. Yes! In fact, in the “open science” community this issue is repeated over and over and over, because people routinely get confused (our audience does not consist of population gen…
On the limits of feathery trees
The NJ tree is from Genome-Wide Analysis in Brazilian Xavante Indians Reveals Low Degree of Admixture. It’s a visualization of a genetic distance matrix. Am I strange, or do these sorts of trees really leave a lot to be desired in terms of actual…
Bearish wisdom!
A few years ago a paper came out which suggested that the brown bears of the ABC Islands of southeastern Alaska were more closely related to polar bears than they were to other brown bears. More precisely, polar bears and ABC brown bears formed a disti…
The continuing tangling of the human tree
Last summer I made a thoughtless and silly error in relation to a model of human population history when asked by a reader the question: “which population is most distantly related to Africans?” I contended that all non-African populations…
Beware of one tree!
Sometimes in the comments of this weblog people get into heated disagreements about one figure and its proper interpretation. I don’t get much involved most of the time because different visualization techniques often differ on the margin, so get…
The paradigm is dead, long live the paradigm!
Mitochondrial DNA and human evolution: Mitochondrial DNA from 147 people, drawn from five geographic populations have been analysed by restriction mapping. All these mitochondrial DMAs stem from one woman who is postulated to have lived ab7out 200,000 years ago, probably in Africa. All the populations examined except the African population have multiple origins, implying that […]
The inevitable social brain
One of the most persistent debates about the process of evolution is whether it exhibits directionality or inevitability. This is not limited to a biological context; Marxist thinkers long promoted a model of long-term social determinism whereby human groups progressed through a sequence of modes of production. Such an assumption is not limited to […]
Toward human phylogenetic intuitions
100 years ago a science based physical anthropology offered up very little as to a systematics of mankind beyond what you could intuit from visual assessments of phenotypic similarity alone. Instead, there were fantastical taxonomies which had little basis in the true pattern of variation and more in the nationalistic debates of that period. The […]
Leaping to a bigger brain
Years ago an evolutionary biologist mentioned to me almost offhand that with the emergence of genomics and the necessity to master computational techniques a lot of the labor hours which may have gone into a more thorough understanding of specific organisms had gone by the wayside. He believed that his Ph.D. advisor was going to […]