Why the âmissing linkâ fossil was almost missed One of the 20th-century's biggest quests was to find the âmissing link,â a being who connected humans to their pre-historic ancestors. It was also the height of scientific racism.
Dr. Paaboâs team also discovered that living, non-African people carry fragments of Neanderthal DNA, a signature of interbreeding from long ago. In May, a team of researchers estimated that Neanderthals and modern humans interbred during a short period of time, between 47,000 and 40,000 years ago.
But some Neanderthal DNA does not fit into this neat picture. The Neanderthal Y chromosome, for example, is more similar to the Y chromosome found in living humans than it is to the rest of the Neanderthal genome.
In 2020, researchers offered an explanation: Neanderthal males inherited a new Y chromosome from humans between 370,000 and 100,000 years ago. But that would have made sense only if a wave of Africans had expanded out of the continent much earlier than scientists had thought.
Researchers have recently found evidence for such an early wave in the genomes of living Africans.
Dr. Tishkoff and her colleagues compared the genome of a 122,000-year-old Neanderthal fossil with the genomes of 180 people from 12 populations across Africa. Previous studies had found no sign of Neanderthal DNA in African genomes. But Dr. Tishkoffâs group detected tiny pieces of Neanderthal-like DNA scattered across all 12 of the populations they studied.
When they examined the size and sequence of those genetic fragments, they concluded that Neanderthals inherited them from early Africans. That meant an early wave of Africans expanded into Europe or Asia about 250,000 years ago and interbred with Neanderthals.
A team of researchers funded by the National Institutes of Health have generated the first complete chromosome sequences from non-human primates. Published in Nature, these sequences uncover remarkable variation between the Y chromosomes of different species, showing rapid evolution, in addition to revealing previously unstudied regions of great ape genomes. Since these primate species are the closest living relatives to humans, the new sequences can provide insights into human evolution.
The researchers focused on the X and Y chromosomes, which play roles in sexual development and fertility, among many other biological functions. They sequenced chromosomes from five great ape species, chimpanzee, bonobo, gorilla and Bornean and Sumatran orangutans, as well as one other primate species that is more distantly related to humans, the siamang gibbon. (...)
The researchers found that over 90% of the ape X chromosome sequences aligned to the human X chromosome, showing that the X chromosomes have remained relatively unchanged over millions of years of evolution. However, only 14% to 27% of the ape Y chromosome sequences aligned to the human Y chromosome. (...)
Meet the man who has transformed our understanding of evolution The Royal Swedish Academy of Sciences has awarded the Canadian evolutionary biologist Dolph Schluter the prestigious Crafoord Prize for his work on the mechanics of evolution, which has fundamentally changed our understanding of how the tree of life branches out.
The Nobel Prize in Physiology or Medicine was awarded to Svante Pääbo on Monday for his discoveries concerning the genomes of extinct hominids and human evolution. (...)
âThrough his pioneering research, Svante Pääbo â this yearâs Nobel Prize laureate in physiology or medicine â accomplished something seemingly impossible: sequencing the genome of the Neanderthal, an extinct relative of present-day humans,â the Nobel committee said in a statement.
âPääboâs discoveries have generated new understanding of our evolutionary history,â the statement said, adding that this research had helped establish the burgeoning science of âpaleogenomics,â or the study of genetic material from ancient pathogens.
Omicronâs Radical Evolution* Thirteen of Omicronâs mutations should have hurt the variantâs chances of survival. Instead, they worked together to make it thrive.
The rules of inheritance are supposedly easy. Dadâs DNA mixes with momâs to generate a new combination. Over time, random mutations will give some individuals better adaptability to the environment. The mutations are selected through generations, and the species becomes stronger. much more
Good morning indeed...I'm already exhausted reading this... So...let's just say they're right, and that the same thing happens in humans. Then, let's assume in a few generations, a really nasty form of COVID comes along, and only those who have been vaccinating (grandparents, parents, individuals) will have the trained epigenetic coding to respond to the "really bad strain"... is it possible we could "breed out" the anti-vaccers? Kids...pick your reproductive partners well!
the precise answer is definitely possibly maybe or theoretically it looks like it if we squint a bit (of course the original article is behind a paywall) seriously, we're finding out more and more regarding epigenetics short answer is that we have a lot of code/dna and we pass it on that code has an on/off function it looks like that certain immune code that gets turned on can be passed on to offspring in the on position biotech is in the early stages of exponential-like discovery writing or modifying biological code has huge potential we'll see what happens and where it goes.. i encourage people to use a platform like twitter to aggregate this type of news most of these companies have a feed to glean for their projects
The rules of inheritance are supposedly easy. Dadâs DNA mixes with momâs to generate a new combination. Over time, random mutations will give some individuals better adaptability to the environment. The mutations are selected through generations, and the species becomes stronger. much more
Good morning indeed...I'm already exhausted reading this...
So...let's just say they're right, and that the same thing happens in humans. Then, let's assume in a few generations, a really nasty form of COVID comes along, and only those who have been vaccinating (grandparents, parents, individuals) will have the trained epigenetic coding to respond to the "really bad strain"... is it possible we could "breed out" the anti-vaccers?
The rules of inheritance are supposedly easy. Dad’s DNA mixes with mom’s to generate a new combination. Over time, random mutations will give some individuals better adaptability to the environment. The mutations are selected through generations, and the species becomes stronger.
But what if that central dogma is only part of the picture?
A new study in Nature Immunology is ruffling feathers in that it re-contextualizes evolution. Mice infected with a non-lethal dose of bacteria, once recovered, can pass on a turbo-boosted immune system to their kids and grandkids—all without changing any DNA sequences. The trick seems to be epigenetic changes—that is, how genes are turned on or off—in their sperm. In other words, compared to millennia of evolution, there’s a faster route for a species to thrive. For any individual, it’s possible to gain survivability and adaptability in a single lifetime, and those changes can be passed on to offspring.
“We wanted to test if we could observe the inheritance of some traits to subsequent generations, let’s say independent of natural selection,” said study author Dr. Jorge Dominguez-Andres at Radboud University Nijmegen Centre.
“The existence of epigenetic heredity is of paramount biological relevance, but the extent to which it happens in mammals remains largely unknown,” said Drs. Paola de Candia at the IRCCS MultiMedica, Milan, and Giuseppe Matarese at the Treg Cell Lab, Dipartimento di Medicina Molecolare e Biotecnologie Mediche at the Università degli Studi di Napoli in Naples, who were not involved in the study. “Their work is a big conceptual leap.”
How Humans Lost Their Tails A new study suggests that a single genetic mutation helps explain why monkeys have tails, while apes and people do not.
For half a billion years or so, our ancestors sprouted tails. As fish, they used their tails to swim through the Cambrian seas. Much later, when they evolved into primates, their tails helped them stay balanced as they raced from branch to branch through Eocene jungles. But then, roughly 25 million years ago, the tails disappeared.
For living species, John Damuth, a biologist at the University of California, Santa Barbara, came up with a mathematical relationship, now known as Damuthâs law, between the average body mass of an animal and its expected population density.
The relationship is not universal but generally holds for large classes of animals like lizards or meat-eating mammals. So, for Tyrannosaurus rex, they had to not only plug in the weight of the dinosaur â about six tons, give or take a few â but also derive other numbers in the law.
