ANTA01H3 Chapter Notes - Chapter 2: Binomial Nomenclature, Georges Cuvier, Carl Linnaeus

100 views3 pages
25 Sep 2017
Chapter 2: The Development of Evolutionary Theory
The Development of Evolutionary Theory
The earliest human ancestors evolved from a species that lived some 5-8 million years ago (Mya). That
ancestral species was the last common ancestor we shared with chimpanzees. In turn, the linage that led to the
apes and ourselves separated from a monkey-like ancestor some 20 Mya. Because evolution takes time, we
rarely witness the appearance of new species except in microorganisms. But we do see microevolutionary
changes in many species.
A Brief History of Evolutionary Thought
The discovery of evolutionary principles first took place in western Europe and was made possible by
advances in scientific thinking that date back to the sixteenth century. Charles Darwin was the first person to
explain the basics mechanisms of the evolutionary process the theory of natural selection. However, a
Scottish naturalist named Alfred Russel Wallace also reach the same conclusion at around the same time.
Natural Selection: The most critical mechanism of evolutionary change. Refers to genetic change in the
frequencies of certain traits in populations due to differential reproductive success between individuals.
Fixity of Species: The notion that species, once created, can never be change; an idea diametrically opposed to
theories of biological evolution.
Precursors to the Theory of Evolution
John Ray
John Ray, a minister educated at Cambridge University in the seventeenth century, developed the concept of
species. He places groups of reproductively isolated organisms into a single category (as it is today). He also
recognized that species frequently shares similarities with other species and grouped these together in a second
level of classification called the genus.
Carolus Linnaeus
The Swedish naturalist is best known for developing a method for classifying plants and animals. He
standardized Ray’s use of genus and species terminology and established the system of binomial
nomenclature. He also added two more categorizes: class and order. His four-level system became a basis for
taxonomy. Another of his innovations was to include humans in his classification of animals. Yet, he also
believed in fixity of species.
Binomial Nomenclature: The convention where the genus and species are used to refer to the species
(scientific name). Ex. Homo Sapiens
Taxonomy: The branch of science concerned with the rules of classifying organisms on the basis of
evolutionary relationships.
Jean-Baptiste Lamarck
He suggested a dynamic relationship between species and the environment such that if the external
environment changed, an animal’s activity would also change to accommodate the new circumstances.
According to Lamarck, these physical changes would occur in response to bodily “needs,” so that if a
find more resources at
find more resources at
Unlock document

This preview shows page 1 of the document.
Unlock all 3 pages and 3 million more documents.

Already have an account? Log in

Get access

$10 USD/m
Billed $120 USD annually
Homework Help
Class Notes
Textbook Notes
40 Verified Answers
Study Guides
1 Booster Class
$8 USD/m
Billed $96 USD annually
Homework Help
Class Notes
Textbook Notes
30 Verified Answers
Study Guides
1 Booster Class