Week Eleven Flashcards
What kind of selection is present in a salmon hatchery?
Choice of brood stock (larger, healthier animals)
- Sperm competition (the “mixed milt” fertilization protocol
- Free-riding fry (less need for egg provisioning)
Relationship between fecundity (eggs/kg) and egg size?
What is the relationship between salmon egg size and survival?
As Egg size increases, the egg number decreases.
As size increases, survival increases.
What is the evolution of egg size in hatcheries?
Reduced egg size in chinook salmon.
- Females favor small egg #’s because they are supplied with tons of food; no need for huge yolk.
- The egg size-survival tradeoff doesn’t matter!
- Equilibrium egg mass because you still want healthy salmon.
Draw Egg mass vs fitness graph, what do the dashed lines mean?
Draw 1988 and 2000 after introduction of salmon.
- so far*
- Higher dashed line means female in hatchery (greater fitness) –> theoretical limit
- Lower dashed line is lower limit when she’s in the wild.
Egg size is declining rapidly, aside from direct selection do the females affect the egg size?
Authors tested for female body size decline and found no evidence that smaller females are driving the decline in egg size.
What are semelparous organisms?
They end their lives with terminal bouts of sex.
- Not the same as rapid ageing but does highlight investment tradeoffs.
What is the semelparity in Antechinus (small marsupials)
Terminal mating strategy: males live just one year.
-Reallocation of resources to sperm and semen production, mate-guarding via extreme copulation duration, and female hyper-polyandry lead to massive physiological collapse
What are the two mating strategies for guppies?
Courtship and consensual mating.
Sneak/forced gonopodial thrusting.
What is the effect of OF in guppies?
Female OF may provide a cryptic means of defence against unwanted sperm, with effects magnified by internal fertilization environment.
What did Carl Smith and Martin Reichard find on Bitterling fish?
They show that female bitterling can significantly improve their fertility with an increase in the number of spawning partners.
- Perform conspicuous behaviors associated with spawning more frequently close to sneakers, and spawn more eggs close to high-quality sneakers.
THE FIRST TIME that females have been shown to engage in behavior that increases the probability of sneaking,.
How are male Parcerius sculpta isopods determined?
- -What are the sizes of each?
- What is the conflict?
The morphs ARE genetically determined; environment plays no role.
-Alphas are largest, beta is next, and gamma is smallest. Female is consistent size (about beta size)
Alpha males hold territories inside small marine sponges.
What is male fitness dependent on for all three isopods (paracerius sculpta)
Who beats who?
Male fitness negatively frequency dependent.
-Gamma best when alpha common, beta is best when alphas have many females in harem.
What is the phenotype of each genetically determined Uta stansburiana (lizards)?
Orange: ultradominant polygamous, territorial
- Chill at higher elevation to show off
Blue: monogamous, territorial
-lower
Yellow: Sneaker
Which lizard beats who?
Orange polygamous beats blue monogamous,
Blue beats yellow sneaker, and yellow sneaker beats red.
- Cycle must be stable; it’s now perfect but there is a natural rhythm.
- Change the frequency and see the effect.
How are mating strategies determined in Ruffs?
How do they care for young?
Male strategies are determined by a single autosomal locus.
There is no parental care of young.
What are the mating strategies of Ruff?
Territorial male ruffs are lekkers (gather together in a competitive display)
- Only 25% successfully gain arena territory in breeding season
- Satellite males consort with territorials, exhibiting homosexual behaviors with each other, which attracts females to the territory.
Who do the female ruffs mate with?
They actually mate with both types of male! Satellite and Territorial.
-They mate with both types more frequently than expected by chance; ruffs have the highest known level of polyandry among birds.
What is the strategy of the Faeder sneaker?
Mimic females and have testes 2-3x larger than the territorial males. Good for sperm competition!!!
-They enter leks with true females, opportunistically mating females when they go into a receptivity crouch.
- They also mount territorial males.
- —-Just how sneaky are they???
Why would some organisms change sex with age?
If to be successful as a male you need to be big (ex. territoriality) why not start out as a female? (=protogyny)
What is the strategy of wrasses?
They change from female to male with age (protogyny)
- -Ovaries are replaced with male equivalent
- In blue-headed wrass, social groups feature a single dominant male who mates with all females.
Which strategies do vertebrates and invertebrates employ for sex changing?
When does this occur?
The male-first strategy is uncommon in vertebrates but well-known in plants and invertebrates.
–Occurs where the fertility advantage to size in female outweighs the advantage of size in sexual selection to males.
What is an exception in the vertebrate/invertebrate sex rule?
CLOWN FISHES
- Biggest member of group is dominant female; second largest is male; other, smaller fish LACK GONADS.
- Loss of dominant female leads to promotion of male to female and of largest immature fish to breeding male.
Potential bonus questions?
- What is the reality TV show in germany?
- Who directed; If you’ve ever wanted to known about sex but was too afraid to ask?
Which country transports “sperm bikes” for semen tansport?
Which species has the longest penis?
The big sperm race on german reality TV
Woody allen
Denmark
Barnicles
-Darwin said “stupendously long organ”
How did Antoine Van Leeuwenhoek discover sperm?
What did he think he saw?
Crafted high-quality microscopes
- Made the first paper about sperm in seminal fluids, BUT he though it was taboo
- Insisted that the sperm came post-copulation.
- Thought he saw nerves and a circulatory system!
- —Sperm made a human???
