Download Biology Notes: Speciation

Name: _________________________________________________ Date: _______________ Period: ________ Biology Notes: Speciation Directions: Fill in the blanks as we cover the topic in the PowerPoint. Corresponds to textbook pages 335 – 337, 343, & 344 ‐ 346 Speciation •
Defined: ____________________ of a _____________ species ______________ an _________________ species •
Species: ____________________ of ____________________ that can ____________________ and produce ____________________ offspring •
Five factors that lead to ____________________: –
Natural Selection –
____________________ flow –
____________________ –
____________________ selection –
Genetic ____________________ Gene Flow (Migration) •
Defined: Movement of ____________________ from 1 ___________________ to ____________________ •
____________________ variations in a population •
Keeps ____________________ populations ____________________ •
If gene ________________ is ____________________ –
No ____________________ (alleles) _______________________ –
Populations are ____________________ –
Organisms __________________ to their ______________________ environment –
Can _________________to ________________________ Reproductive Isolation •
When populations are ____________________ for a ___________ time… gene flow ____________________ •
When populations can ______________ longer _______________ or _____________ longer reproduce ____________________ offspring •
____________________ step in the ____________________ of a __________ species Additional Information What can cause reproductive isolation? 1) Geographic Isolation: o Organisms _______________ by geographic ______________ 2) Behavioral Isolation o Organisms ____________________ by ____________________ mating ____________________ 3) Temporal Isolation o Organisms ____________________ by differing ____________________ of ____________________ Genetic Drift •
Defined: ____________________ in allele ____________________ due to ____________________ –
•
____________________ natural selection Bottleneck effect –
More likely in ____________________ populations –
Results in a ____________________ of genetic ____________________ (alleles) –
Example: Natural ____________________ •
Pre‐forest fire: Green is ____________________ adapted (____________________ better) •
Post‐forest fire: ____________________ more likely to ____________________ –
Survival ____________________ to ____________________ Review 1) What is speciation? 2) What leads to speciation? 3) What is gene flow? 4) What happens if gene flow is prevented? 5) How are temporal, behavioral, and geographic isolation different? 6) How are temporal, behavioral, and geographic isolation similar? 7) What are the 5 factors that lead to evolution? Geographic Isolation Examples Behavior Isolation Examples Temporal Isolation Examples