CHDV 23249 Lecture Notes - Lecture 10: Pair Bond, Gene, Parental Investment
1 Feb 2017
School
Department
Course
Professor
Mating System
Friday, January 27, 2017
10:29 AM
Midterm on February 3rd
Last Names A-L BSCL 001
Last Names M-Z BSLC 205
Final Exam March 15 at 10:30-12:30
Matins Systems: patterns of male-female associations for breeding purposes
number of mates for each sex
how many mates are attracted, chosen, defended
characteristsics of male-female pair-bonds
o pair-bonds: an ongoing association, beyond just copulation, b/w male and female for
breeding purposes
mutual attraction or dominance
Example: Albatross
doesn't mean absolute loyalty, nor does it mean that you only have one pair bond
at a time
So why aren't all species in one male group with multiple females?
parental investment differ.
ecological factors diff.
evolutionary history differ.
Factors affecting mating system:
Species
o parental investment
o population sex ratio
o population size
Ecological
o food density and distribution
o length of breeding period (short time in artic, longer time in warmer areas, more
resources)
o predators
Evolutionary History
o constraints in time for selection to cause changes
TYPES OF MATING SYSTEMS
Promiscuity
Males and females mate without forming pair bonds
o selective mating (not random)
o males only contribute genes to offspring (no direct benefits, not increasing females'
fitness)
o Ex: Scramble Competition Mating: Typically evenly distributed mates or resources,
inability to control resources
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Matins systems: patterns of male-female associations for breeding purposes. How many mates are attracted, chosen, defended characteristsics of male-female pair-bonds: pair-bonds: an ongoing association, beyond just copulation, b/w male and female for breeding purposes. Doesn"t mean absolute loyalty, nor does it mean that you only have one pair bond at a time. Species: parental investment, population sex ratio, population size. Ecological food density and distribution length of breeding period (short time in artic, longer time in warmer areas, more resources: predators. Evolutionary history: constraints in time for selection to cause changes. Hot spot (males aggregates where females are most likely to be encountered) Hot shot (males aggregate where the most successful male is) Diluted predation risks reduction of female mating effort. Males offer no (non-genetic) resources to females or their offspring (vs. economic mating system) Multigenic control sexually selected traits show large additive genetic variation. Mutation at any of these genes will lead to genetic variation.
