Comparative Anatomy Ch. 1 Lecture 1

Comparative Morphology

A branch of biology focusing on the functional significance of anatomical variations among (intra) and between (inter) individuals or species

What does intra in comparative morphology mean?

Difference between same species

What does inter in comparative methodology mean?

Difference between different classes of animals

Comparative Approach

A tool that provides a structural framework for comparison

What are comparisons based on?

Functional and evolutionary significance

What does functional significance (functional morphology) look at?

Looks at how biological animal parts works today in the current environment

What does evolutionary significance (evolutionary morphology) look at?

Looks at the historical lineage of species

Guides analyses and hypotheses development regarding animal design

Comparative Approach

-cercal

Kerkos tail

Diphy-

Double

Hetero-

Another

Homo-

Same

Proto-

Initial/first

Heterocercal

Protocercal

Diphycercal

Homocercal

Vertebrate Morphology

Seeks to explain the processes that lead to structural and functional differences

Evolution

Inherited changes in a population of organisms over time leading to the appearance of new forms

Speciation

The process by which new species or populations of living things develop from preexisting species

These concepts of evolution were presented long before_______but explanations of evolutionary mechanisms were not understood

Darwin (3000 years ago)

Linnaean System

Carol Linnaeus developed a system of nomenclature of plants and animals that is still used today

Who is a predominant Swedish medical doctor who gave up the practice to study plants and animals?

Carol Linnaeus

What did Carol Linnaeus philosophically argue (1707-1778)?

Argued that species were unchangeable and their characteristics were divinely created

Evolution by inheritance of Acquired Characteristics

Species change throughout their lifetime

What are the 3 basic beliefs of Acquired Characteristics

Lowly species evolved spontaneously, evolution proceeds towards perfection (human), change is driven by the needs experienced during a single lifetime

The philosophy of evolution by inheritance of acquired characteristics

Jean-Baptiste de Lamarck (1744-1829)

Charles Darwin (1809-1882)

Created the theory of Finches on the Galapagos Island. Spent 5 years as the ship (H.M.S. Beagle) naturalist collecting and documenting characteristics of animals (Evolution by natural selection)

Also a naturalist (like Darwin) but not financially privileged. Collected and sold biologically specimens, primarily from the Amazon and Malaysia. Developed a theory of evolution by natural selection independent of Darwin (waited 20+ years to publish). Lost much of his work in a ship fire in 1852 and did not have the resources to procrastinate.

Alfred Wallace (1823-1913)

Son of a swiss minister. Founded the Museum of Comparative Zoology at Harvard 1860 and the American Academy of Sciences & the Smithsonian Institute. Did not believe in evolution. First to suggest the occurrence of “Ice Ages”

Louis Agassiz (1807-1873)

Three-Fold-Parallelism

Believed that variations in living organism reflected differences in the development stages

Stephen J. Gould (1941-2002)

Evolutionary Biologist, Paleontologist, and Science Historian

Phyletic gradualism

Bad genes are eliminated gradually over time

Punctuated equilibrium

Catastrophic events occur eliminating some genes and population evolve to fill that niche (bad genes vs bad luck)