When the eggs are ready the funnel squirts them out into the water. The little oval shaped eggs have glassy shells, and the mother does not leave them until the babies are hatched. For maybe three long months she guards them and never leaves them, not even to eat. At last the eggs hatch into miniature babies just like their mother. The eggs of the. Big mothers lay eggs one inch long that hatch into one inch baby octopuses. A mother octopus lays thousands of eggs. The Atlantic octopus may lay l80, eggs and the job may take her two weeks.
She sticks them to a rock and stands guard. Her work is done when the newborn babies swim off into the sea. How big is a baby octopus? Who's Online. Octopuses live short, lonely lives. Even the big ones only see a few years. And that usually means only one shot at creating the next generation —and they don't have time for parenting.
So they up the odds of passing along their genetic legacy by making lots of babies, as in thousands and thousands of babies. Female octopuses lay their eggs and painstakingly weave them together into strands. They then sit guard for weeks, months and sometimes as long as a year. During this time they don't seem to eat much, and their main preoccupation is keeping their eggs aerated and clear of algae, which they do by blowing water over them and cleaning them delicately with their suckers.
At the end of the brooding period, nearly all of the octopus young hatch at once, creating a marvel for those lucky enough to witness it. One diver in Puget Sound captured one impressive giant Pacific octopus Enteroctopus dofleini brood hatching on film last week.
The water, about 30 meters below the surface, was filled with tiny baby octopuses, swimming up and away from their mother seen tucked away in a den with additional strands of eggs.
Although only millimeters long at hatching, these octopuses can grow to be adults weighing more than 15 kilograms and with an arm span of more than four meters. After leaving their egg casings , these hatchlings will swim toward the surface and join other small animals in a planktonic stage.
Wang was a part of that research team and has continued building on that foundation for her PhD thesis. In the new study, she used the same California two-spot octopuses to study their odd maternal behaviors. Mature, non-mated females are active predators who spend a lot of time outside their dens and quickly pounce on prey-like fiddler crabs. In the first stage of brooding though, mated females sit with their eggs like a deep-sea hen, stroking them and blowing water over the clutch.
For the first three or four days they continue feeding but rarely leave their eggs, snatching the odd unlucky crab only if it happens to get too close. After four days or so, they stop eating completely.
This stage of brooding can last eight to ten more days until they hit the final phase of rapid decline, when things get really ugly. The females become listless, spending more time away from their eggs or slamming themselves against the corners of the tank. They start grooming themselves excessively, running their arms over their mantles until they became a tangled mess. Their skin pales and they lose muscle tone, even beyond what you would expect to see in a starving octopus.
Wang, who has made pets out of some of the octopuses in the lab, said, "This is troubling to even witness in the lab, because from a human perspective they look like they're self-mutilating. It's just very, very strange behavior. Wang collected the optic glands from octopuses at each phase and sequenced the RNA transcriptome of each.
RNA carries instructions from DNA about how to produce proteins, so sequencing it is a good way to understand the activity of genes and what's going on inside cells at a given time. During the non-mated phase when females were actively hunting and eating, they produced high levels of neuropeptides, or small protein molecules used by neurons to communicate with each other that have been linked to feeding behavior in many animals. After mating, these neuropeptides dropped off precipitously.
As the animals began to fast and decline, there was more activity in genes that produce neurotransmitters called catecholamines, steroids that metabolize cholesterol, and insulin-like factors. Wang said finding activity related to metabolism was surprising because it's the first time the optic gland has been linked to something other than reproduction. Just how these molecular and signaling changes cause the different behavioral changes is unclear though.
Females in the early stage of brooding continued to eat but didn't actively seek out food. This could mean that the neuropeptides affect the amount of energy the octopus expends to find prey. Certain muscles may begin to deteriorate so the octopus physically can't hunt or digest food.
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