Genetic evidence (5) Flashcards
The strong similarities between humans and the
African great apes led Charles Darwin in 1871 to
predict that ___ was the likely place where the
common ancestor of African apes and humans
came from.
Africa
Which bit of genetic evidence supports the notion that Africa was the likely place where the common ancestor of African apes and humans
came from?
Both chromosomal DNA and mitochondrial DNA
(mtDNA) evidence supports this daring prediction
made almost 150 years ago, as do the fossils.
What does the comparison of nuclear DNA show?
The comparison of nuclear DNA (or genes)
of two hominids shows how related they are.
The more genes they share the more closely
they are related.
- All humans share about ___% of the same genes, showing their obvious close relationship.
- Humans and apes share between ___% and ___% of the same genes.
- Of the apes, the _____ (African ape) shares the most genes with humans (98.8%), making them the closest relative to humans.
This close relationship shows that humans and apes must not only have had a common ancestor but that this ancestor must have been ape-like.
- 99.9%
- 96.9% and 98.8%
- chimpanzee
What does the comparison of hominid mtDNA show?
Shows how long ago humans and African apes shared a common ancestor.
What does the number of differences in the mtDNA of two species show?
The number of differences in the mtDNA of two species tells scientists not only how related the species are but how long ago they separated. If there are few differences, the species separated recently. If there are many differences, the species separated long ago.
Genetics are proving invaluable in gaining a better understanding of human evolution. Geneticist can:
cist can:
- by comparing the nuclear DNA of hominids see how related they are.
- by comparing the mtDNA of hominids show:
- that humans evolved from ape-like ancestors.
- the approximate age when the evolutionary paths of the various hominids diverged.
