The DNA evidence informs this conclusion, and the fossils do, too.
Hardly ever has a scientific prediction so bold, so ‘out there’ for its time, been upheld as the one made in 1871 – that human evolution began in Africa. The African great apes, including humans, have a closer kinship bond with one another than the African apes have with orangutans or other primates. The DNA evidence shows an amazing confirmation of this daring prediction. The strong similarities between humans and the African great apes led Charles Darwin in 1871 to predict that Africa was the likely place where the human lineage branched off from other animals – that is, the place where the common ancestor of chimpanzees, humans, and gorillas once lived. The human evolutionary tree is embedded within the great apes. The DNA evidence leaves us with one of the greatest surprises in biology: the wall between human, on the one hand, and ape or animal, on the other, has been breached. From the perspective of this powerful test of biological kinship, humans are not only related to the great apes – we are one. No matter how the calculation is done, the big point still holds: humans, chimpanzees, and bonobos are more closely related to one another than either is to gorillas or any other primate. When these differences are counted, there is an additional 4 to 5% distinction between the human and chimpanzee genomes. A comparison of the entire genome, however, indicates that segments of DNA have also been deleted, duplicated over and over, or inserted from one part of the genome into another. The 1.2% chimp-human distinction, for example, involves a measurement of only substitutions in the base building blocks of those genes that chimpanzees and humans share. Geneticists have come up with a variety of ways of calculating the percentages, which give different impressions about how similar chimpanzees and humans are. How do the monkeys stack up? All of the great apes and humans differ from rhesus monkeys, for example, by about 7% in their DNA. A difference of 3.1% distinguishes us and the African apes from the Asian great ape, the orangutan.
Most importantly, chimpanzees, bonobos, and humans all show this same amount of difference from gorillas. The DNA difference with gorillas, another of the African apes, is about 1.6%. The bonobo ( Pan paniscus), which is the close cousin of chimpanzees ( Pan troglodytes), differs from humans to the same degree. While the genetic difference between individual humans today is minuscule – about 0.1%, on average – study of the same aspects of the chimpanzee genome indicates a difference of about 1.2%. The amount of difference in DNA is a test of the difference between one species and another – and thus how closely or distantly related they are. DNA shapes how an organism grows up and the physiology of its blood, bone, and brains.ĭNA is thus especially important in the study of evolution. It also consists of the molecular codes that regulate the output of genes – that is, the timing and degree of protein-making. It consists of genes, which are the molecular codes for proteins – the building blocks of our tissues and their functions. DNA, or deoxyribonucleic acid, is the molecule that makes up an organism’s genome in the nucleus of every cell. The same is true for the relationships among organisms. Through news accounts and crime stories, we’re all familiar with the fact that the DNA in our cells reflects each individual’s unique identity and how closely related we are to one another. Science, Religion, Evolution and Creationism: Primer.Members Thoughts on Science, Religion & Human Origins (video).Teaching Evolution through Human Examples.
#Picture of chimpanzee and gorilla archive#
Digital Archive of Ungulate and Carnivore Dentition.Adventures in the Rift Valley: Interactive.Smithsonian National Museum of Natural History The Smithsonian Institution's Human Origins Program Main Menu
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