UW-Madison BIOLOGY 101 - Speciation and Macroevolution (2 pages)

Previewing page 1 of 2 page document View the full content.
View Full Document

Speciation and Macroevolution

Previewing page 1 of actual document.

View the full content.
View Full Document
View Full Document

Speciation and Macroevolution


Lecture number:
Lecture Note
University of Wisconsin, Madison
Biology 101 - Zoology 101: Animal Biology
Documents in this Packet
Unformatted text preview:

Zoology101 Animal Biology Last Lecture Outline 1 Conservation 2 Sexual selection Lecture 36 Current Lecture 1 Evolutionary trap 2 Speciation and Macroevolution Evolutionary Trap An organism uses particular set of cues in order to make a choice Cue produces information presumably associated with a particular outcome successful reproduction Speciation and Macroevolution What is speciation Evolution of a new species Macroevolution evolutionary change above the species level the evolutionary components of speciation Microevolution change in allele frequency in a local population in time What is a species Not simple to define Biological species concept individuals are members of the same species if they are capable of interbreeding and producing fertile offspring BSC often used but may not work in all cases Asexually reproducing species Ecological species concept Niches Morphological species concept Similar size and shape same species Reproductive isolation key component of BSC the existence of biological factors reproductive behaviors that prevent 2 individuals from interbreeding and producing a viable offspring a single barrier may not necessarily lead to reproductive isolation many barriers act in concert Zygote fusion of sperm and egg Barriers can be prezygotic or post zygotic pre preventing mating prevent fertilization mechanical isolation mating may be attempted but prevented by morphological differences gametic sperm of one species may not be able to fertilize the eggs of another species Post anything after the zygote has formed reduced hybrid viability offspring don t survive well Hybrid breakdown hybrids are nonviable or sterile in subsequent generation Speciation occurs in 2 ways Allopatric geographic separation of population rivers islands Divergence greatly reduced gene flow genetic drift founder effect Natural selection Sympatric Not covered in class yet

View Full Document

Access the best Study Guides, Lecture Notes and Practice Exams

Loading Unlocking...

Join to view Speciation and Macroevolution and access 3M+ class-specific study document.

We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Speciation and Macroevolution and access 3M+ class-specific study document.


By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?