Lesson 9-11 Flashcards
How is the molecular clock hypothesis used to estimate the passage of time?
Assuming that neutral changes in DNA code occur at a constant rate, by looking at the differences between populations and species can used to look at the passage of time.
How are primates defined
Mammals distinguished with through their grasping hands, nails rather than claws, and stereoscopic vision.
When is estimated that the hominid lineage diverged from chimps?
6-7 million years ago.
How can the presence Endogenous retroviruses be used to as evidence to determine the last common ancestor?
Retroviruses sometimes find their way into host DNA, though this is rare and random. The same placement on the same chromosome indicates common ancestry.
Where did human’s most likely evolve?
The Congo basin.
When did our ancestors become recognizably human like?
Approximately 2 million years ago.
When did modern humans emerge?
100-150,000 years ago
What was the first species to leave africa?
Homo Erectus
Ancestral humans left Africa in multiple waves, how has this effected the genes present in modern humans.
During the last migration modern humans interbred with neanderthals and denisovans . As a result there are varying degrees of neanderthal genes present in modern humans today. Sub-Saharan have the most, Europeans and Asians the least.
How have humans been effected by migration away from afrotropics
Lighter skin and relatively rounder and shorter.
