Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

9 Cards in this Set

  • Front
  • Back
Allopatric speciation
Speciation that occurs when the initial block to gene flow is a
geographical barrier that physically isolates the population (i.e. mountain ranges, movement of
glaciers, formation of land bridges, subsidence of large lakes).
Adaptive radiation
The evolution of many diversely adapted species from a common

i.e. darwin's finches
Sympatric speciation
chromosomal changes in plants, non random mating alter gene flow. genetically isolated even tho their ranges over lap

Formation of new species within the range of parent populations.

Reproductive isolation evolves without geographical isolation.
• This can occur quickly (in one generation) if a genetic change results in a
reproductive barrier between the mutants and the parent population.
The geographical distribution of species
change in a trait due to geological factor

One type of geographical variation that is a graded change in some trait
along a geographic transect. (For example, the average body size of many North American mammal
species gradually increases with increasing latitude. It is presumed that the
reduced surface area to volume ratio associated with larger size helps
animals in cold environments conserve body heat.)
population genetics
Emphasized genetic variation within populations and recognized the
importance of quantitative characters

Was an important turning point for evolutionary theory, because it reconciled
Mendelian genetics with Darwinian evolution
Gene pool
The total aggregate of genes in a population at any one time
geographical variation
differences in genetic structure btwn populations

affected by nat. selec. and genetic drift
when two or more of a discrete trait are represented in a population