3. Sexual Selection Flashcards
What is Darwin’s definition of sexual selection
A special case of natural selection related to the evolution of sexual characteristics
What are primary sexual characteristics
Differences in male and female genitalia
What are secondary sexual characteristics
Traits that attract mates competition or attraction
what are the two categories of sexual selection
intrasexual selection and intersexual selection
what is intrasexual selection
same sex competition for mating/reproduction
what is intersexual selection
members of one sex choose the opposite sex member for mating/reproduction
What is the Bateman’s principle
females are choosy and males are indiscriminate; variation in male reproductive success; degree of parental investment is inversely related to reproductive success
sexual selection is strong in what mating system
polyandrous and polygamous species
what puts greater pressure on secondary sexual characteristics
greater variation in reproductive success
what are the four classes of evolutionary models based on female choice
direct benefits; good genes; runaway selection; sensory exploitation
female mate choice theory is under what control
genetic control; behavior is linked to reproductive success
what is the Zuk-Hamilton model of parasite resistance
traits that are true indicators of genetic quality are superior
what is the major histocompatibility complex
self vs. foreign cell identification; females prefer mates with complementary MHC
what type of male do choosy females prefer
elaborate males
what type of male do non choosy females prefer
no preference
why is a male trait important in sensory bias and mat choice
it elicits a prior held sensory/neurobiological bias, then it becomes associated with mate choice secondarily
what is sexual imprinting
early social experience that affects species recognition in adults during courtship and mating
what are the types of imprinting
filial; sexual; chemical
what is mate choice copying
female preferences is affected other female choice in population
what is the curvilinear function
immature and older males show lower reproduction rates than males at peak physical fitness
what are honest indicators of strength in red deer
length of vocal tract predictor of body size
what are alternative strategies for male-male competition
males show phenotypic variation
what are examples of cuckoldry in blue gill sunfish
parental males hold and defend territories; sneaker males resemble parental type but do not hold territory; satellite males resemble females
how is sperm different in parental males and sneaker males
parental males invest in fewer high quality sperm where as sneaker males invest in many short lived low quality sperm