Evolution & The Fossil Record Flashcards
What is the Catastrophe Theory?
Floods and earthquakes must have periodically killed off organisms in parts of the world
New organisms from other parts of the world moved in to repopulate these regions
What is Evolution?
The continuous genetic adaptation of organisms or species to their environment.
Fossils?
The remains of or trace of the presence of an ancient organism.
(Two types: body & trace fossils)
Body fossil
Preserved remains of an ancient organism.
Trace Fossil?
Indication of the presence of an ancient organism.
What is replacement?
During fossilization bones are covered into solid rock
Lemarckian Evolution (transmutation)
• Jean Baptiste Lamarck (1744-1829): physical characteristics were acquired due to inner needs and inherited by future generations (transmutation)
Natural Selection
Process by which favorable traits become common and unfavorable traits become less common in successive generations of a population.
What are Homologous Structures?
body parts of similar origin, structure, and development but adapted for different functions.
(derived from the same structures in the embryo)
○ Ex. Limb structures
What are Vestigial Organs?
reduced or useless structures in
plants or animals that are useful in other organisms.
○ Human appendix
○ Human tail bone
○ Whale pelvis
What is Biochemistry?
study of chemical processes in living organisms): the metabolism of vastly different organisms is based on the same complex biochemical compounds
What is mutation
permanent inheritable change in genetic material within cells. (creates variation in the gene pool)
What is Speciation?
The origin of a new species from two or more individuals of a pre-exsist inc one.
What is a species?
Group of individuals capable of interbreeding and producing fertile off spring.
What’s is Allopatric Speciation?
process through which populations of the same species are physically isolated (due to geographic barriers) and evolve separately
What is Sympatric Speciation?
process by which new species evolve from a single ancestral species inhabiting the same geographic region
Speciation through biological isolation
Phyletic Gradualism
Species continue to adapt to new environmental & biological conditions overtime, gradually becoming new species.
Punctuated Equilibrium
Proposes that species split into two distinct species rather than one species gradually transforming into another (phyletic gradualism)
What is Convergent Evolution
process where organisms not closely related independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.
Divergent Evolution
process by which a species diverges into two or more descendant species resulting in once similar species becoming more and more dissimilar.
Cope’ Rule
Body size increases during the evolution of a species.
Evolutionary Radiation
Rapid expansion of a species over a relatively short period of time.
Adaptive Breakthroughs
Appearance of key features or traits that allow the species to succeed.
Extinction events
The death of one species can present opportunities for another one. Ex.
