Sponge spawning. Coral spawning - sperm Coral spawning - eggs.
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Transcript of Sponge spawning. Coral spawning - sperm Coral spawning - eggs.
Sponge spawning
Sponge spawning
Coral spawning - sperm
Coral spawning - eggs
Coral spawning - eggs
Palolo worm (polychaete annelid)
Consist of anterior atoke and a posterior epitoke
On two or three nights, epitokes break free from the atokes and swim to the surface
Mass spawning of palolo worms
Palolo worms swarming
Palolo worms
Palolo worms
Uterine horns in some mammals
Acanthocephalans (spiny-headed worms
Acanthocephalan in situ
Acanthocephalan reproduction
Males have an eversible penis After mating with a female, the males
neatly cap the female gonopore with cement
Males will also attempt to cement shut the gonopores of other males!
Last male advantage
In a number of animals with internal fertilization, the last sperm to enter the female reproductive system have the advantage
Examples are birds and insects
Damselflies mating
Dragonflies mating
Dragonflies and damselflies Male curls his abdomen to transfer sperm
from the ninth abdominal segment to accessory genitalia on the second abdominal segment
The male and female adopt the wheel position to transfer sperm to the female
Before copulating, the male will scoop out any pre-existing sperm from the female’s reproductive tract
Males sometime hold on to the female while she oviposits
Other males hover around the female during oviposition
Onychophora
Onychophora reproduction
Male deposits a spermatophore (a protective structure enclosing sperm) on the forest floor
A female stumbles across a stomatophore and appresses her ventral side to the spermatophore
The spermatophore causes her ventral body wall to rupture (ouch!), providing a means for sperm to enter her body