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Flashcards in Speciation Deck (18):
0

2 isolation mechanisms

Pre-zygotic
Post-zygotic

1

Pre-zygotic

Prevents continuation of species before the zygote is made

2

Post-zygotic

Prevents continuation of species after zygote is made

3

5 types of isolation of populations

Behavioral
Geographic
Temporal
Mechanical/gametic
Hybrid infertility or inviability

4

Behavioral isolation

Organisms won't mate if they aren't attracted to another (pre-zygotic)

5

Geographic isolation

Physical barriers divide a population (pre-zygotic)

6

Temporal isolation

Species breed at different times, day or night, different seasons (pre-zygotic)

7

Mechanical isolation

Members of different populations cannot mate successfully, not compatible (pre-zygotic)

8

Gametic isolation

Sperm and egg cannot form a zygote (pre-zygotic)

9

Hybrid infertility

Fertilization occurs but offspring are not able to have offspring (post-zygotic)

10

Hybrid inviability

Fertilization occurs but offspring aren't able to survive (post-zygotic)

11

Requirements for extinction

Organisms don't have to be perfect only ones that are the best for survival

12

_____% of species that once lived are extinct

99

13

A typical lifetime is ______ years for a species

1 million

14

2 types of extinction

Background
Mass

15

Background extinction

Occurs continuously at a very low rate, happens to a few species in a small area, caused by local changes in an environment

16

Mass extinction

Destroys many specie at a global level, caused by catastrophic events

17

There's has been at least ____ mass extinctions in the last ______ years

5 ; 600 million