Living Environment Translated English 2014 | Page 37

18. Vestigial structures- a structure that doesn’t seem to have a
function , and may once have functioned in the body of an
ancestor
19. Primates- a group of mammals including humans , monkeys, and
apes that share characteristics such as opposable thumbs,
binocular vision, and flexible shoulders
20. Hominids- a humanlike primate that appeared about 4-6 million
years ago, ate both plants and meat, and walked upright on two
legs
21. Homo sapiens- early humans that likely evolved from CroMagnons
22. Cro-Magnon - an early human group that appeared about
40,000 years ago and are thought to be direct ancestors of
modern humans.
23. Neanderthals- an early human group that had short, heavy
bodies with thick bones, small chins, and heavy brow ridges.
They appeared about 125,000 years ago and disappeared about
30,000 years ago.
24. Paleontology- the study of fossils or extinct organisms
25. Gene pool- a collection of alleles ( genes) found in all the
individuals of a population
26. Speciation- the evolution of two or more species from one
ancestral species
27. Extinction- elimination of a species from the Earth
B. General Notes
1. Evolution is one of the central ideas of biology. It explains how
living things have changed in the past and is the basis for
predicting how they might change in the future.
2. Evolution is change in the characteristics of a species over time.
3. There are two model about the speed of evolution :
a. Gradualism- a model that describes evolution as a slow
process by which one species changes into a new species