What is the Bateman model?
Bateman’s principle, which states that male reproductive success should increase with multiple mating, whereas female reproductive success should not, has long been used to explain sex differences in behavior.
What did Bateman conclude about the roles of males and females in reproduction?
Bateman concluded that, because single ova are more costly to produce than are single sperm, the number of offspring produced by a female fruit fly was limited mainly by her ability to produce eggs, whereas the reproductive success of a male was limited by the number of females that he inseminated.
What is the Bateman gradient?
Bateman focused mainly on the second series of data when discussing his results. His main conclusion was that the reproductive success of females does not increase with an influx of mates, as one fit mate was enough to successfully complete fertilization. This is often referred to as Bateman’s Gradient.
What is Bateman Trivers hypothesis?
The Trivers-Willard hypothesis can be seen as a corollary of the Darwin-Bateman paradigm. Because sexual selection is believed to act more strongly on males, such characteristics as size, health, and strength would be expected to be more important for reproductive success in males than in females.
Which is an example of Anisogamy?
For example, large males are sexually selected for in elephant seals for their large size helps the male fight off other males, but small males are sexually selected for in spiders for they can mate with the female more quickly while avoiding sexual cannibalism.
Why is male parental care so rare in nature?
The evolution of male parental care is particularly rare in non-monogamous species because predominantly, investing effort into mating is more evolutionarily-effective for males than providing parental care.
In what situation can cryptic female choice enhance the fitness of a female?
A female may exercise cryptic female choice by determining whether a male can mate for longer or for shorter periods of time, thus increasing or decreasing male insemination success. In hanging flies, females allows males that provide larger nuptial gifts to copulate longer, which increases male fitness.
Why do females have more parental investment than males?
Females, because they produce eggs, make a larger parental investment prior to mating. Males can replenish their gamete supply and return to the mating pool sooner than females because they produce small, cheap sperm rather than large, costly eggs.
What is the difference between intersexual and intrasexual selection?
In intersexual selection, one sex, typically the males, will display a certain trait or behavior with the goal of attracting and mating with the opposite sex. Intrasexual selection, on the other hand, occurs between members of the same sex. For example, male sea lions compete for dominance over rookeries of females.
Can someone produce no gametes?
Some people never produce gametes in their entire lives. The rest of us don’t start producing them until puberty and some of us stop again.
https://www.youtube.com/watch?v=SH5R2G39I9c