One difference the researchers discovered is a gorilla gene that probably helps the animal's skin grow a tough layer of keratin-a protein that makes up fingernails-on their knuckles, which aids in the animal's distinctive knuckle walk. Humans seem to lack this genetic variant.Īnother is in sperm genes-in humans, a specific gene enables sperm to compete with those of other males. "But it's the few that differ that are of particular interest here." So that means most of our genes are very similar, or even identical to, the gorilla version of the same gene," said Chris Tyler-Smith, a geneticist at Wellcome Trust. "The big picture is that we're perhaps 98 percent identical in our sequences to gorillas. The gene discoveries also offer new riddles in primate-and human-evolution. We can't just conform to a simple tree on a gene-by-gene basis." "It means within each branch things can happen. What this does show is that each branch has it own complexities and challenges," said Richard Gibbs, a geneticist at Baylor College of Medicine's Human Genome Sequencing Center, who wasn't involved in the study. "This doesn't change the overall view of evolution, and the overall tree is still the same. (See "Orangutans May Be Closest Human Relatives, Not Chimps". Humans and chimps then popped off of that lineage some 6 million years ago, according to the new study.Īnother surprising result is that part of the gorilla genome is at odds with the current structure of the great ape evolutionary tree.įor example, instead of gorillas being most similar to chimps and then humans in that portion of the DNA, the branches flip to humans being most similar to gorillas and then chimps. A single base pair of primate DNA, for example, has a roughly one-in-a-billion chance of mutating each year-which means genetic differences in a pair can help estimate when a split occurred. ( Get a genetics overview.)Īccording to the new genetic research-when combined with known fossils-the lineage that led to humans, chimps, and gorillas evolved from a common ancestor about 10 million years ago. Thankfully for the scientists, pairs of DNA letters called base pairs mutate at a fairly regular pace. Tracing exactly when these lineages diverged, however, is tricky. Primatologists know from fossils that humans, chimps, and gorillas shared an ancient ancestor. "Although of the human genome is indeed closer to chimpanzees, on average, a sizable minority of 15 percent is in fact closer to gorillas, and another 15 percent is where chimpanzees and gorillas are closest," said geneticist Aylwyn Scally, a study co-author also at the Wellcome Trust. (See "New Ape May Be Human-Gorilla Ancestor.")īut Durbin and a team of 70 other researchers didn't stop with a family tree comparison. The team also detected groups of gorilla genes that were surprisingly similar to human genes. "Based on the comparisons between them, it helps us explore the evolutionary origins of humans and where we separated from other great ape species in Africa between six and ten million years ago," Durbin said. So we now have a complete picture," said study co-author Richard Durbin, a geneticist with the U.K.'s Wellcome Trust Sanger Institute. probably one percent of the whole genome. "Previously, people had some sort of picture based on. In 2008 geneticists took DNA from Kamilah, a then 30-year-old female western lowland gorilla from the San Diego Zoo.įour years later the team published the species' genome, which completes a basic genetic library of the great apes-a branch of primates including people, chimpanzees, gorillas, and orangutans. spectrum of interactions among sympatric chimpanzees and gorillas includes extended bouts of play among young individuals.Staring face to face with a gorilla, it's hard not to find them eerily similar to humans-and now the first published gorilla genome supports that, according to a new study. Our current research is unravelling the environmental phenomena and the dynamics of chimpanzees and gorillas associated shared strategies and promises to reveal a greater depth to their social awareness than previously imagined. On many occasions, chimpanzees and gorillas feed in close proximity and engage in a range of social interactions, including social play, sexual interactions and spread of information. Over the course of this project we have documented a variety of contexts and revealed a greater diversity of interactions than previously recognized. The Goualougo Triangle is the only site to habituate both species of apes to the presence of human observers, providing a unique opportunity to study interactions between these two great ape species. Observations of interspecific interactions between these species are however rare and often fleeting. Chimpanzees reside in sympatry with western lowland gorillas throughout much of western equatorial Africa.
0 Comments
Leave a Reply. |