m Flashcards
What is sexual cannibalism?
Mating behaviour is where one mate (typically the female) eats the other during or after mating.
Which species are most known for sexual cannibalism?
Black widow spiders and praying mantses.
How di male spiders reproduce without a penis?
They create a sperm web, deposit sperm on it, gather it in their pedipalps, and insert it into the female’s sperm receptacle.
What is the sperm receptacle in spiders?
A long, coiled tube in the female that stores sperm and connects to the oviduct.
How do mantids mate?
The male climbs on the female’s back, twists his abdomen, and deposits sperm into her spermatheca.
What is a spermatheca?
A sac-like organ in female mantids used to store sperm.
What is an ootheca?
A protective foam egg mass laid by female mantids that hardens over time.
What is the Mistaken identity hypothesis?
The female mistakes the male for prey; this usually happens before mating.
what is the stressed female hypothesis?
Females in stressful lab conditions are more likely to cannibalize; cannibalism may happen before, during, or after mating.
What is the Aggression Soill-over Hypothesis?
Female territorial aggression causes her to attack the male before mating.
What is the adaptive foraging hypothesis?
Cannibalism provides nutrition that can help females produce more or healthier offspring.
What evidence supports the adaptive foraging hypothesis?
Hungry female mantids and red-back spiders who cannibalize often lay more eggs.
What is the Mate Choice Hypothesis?
Females may cannibalize lower-quality males (ex: poor dancers or asymmetrical traits) before mating.
What is the Mate Guarding Hypothesis?
Males increase paternity chances by being consumed, preventing the female from mating again.
What is a “mating plug”?
A male spider’s pedipalp breaks off in the female’s sperm receptacle, blocking other males from mating.
What is the sperm transfer hypothesis?
Being eaten prolongs mating time, helping males transfer more sperm.
Why do Red-backed Spiders engage in sexual cannibalism?
Males have higher fitness if they copulate longer; cannibalism helps prolong mating.
Can males be cannibals too?
Yes, in species like Micaria socialbilis, males cannibalize females 20% of the time.
Why do Mivaria sociabilis males cannibalize more in the summer?
In summer, there are fewer males and many females, sp males can afford to be picky and consume lower-quality females.
