Scientists have discovered that the female southern bottle tail squid actually eats the sperm of its partner during mating, which has never been seen before in a cephalopod, according to Science World Report.
While this behavior is unique to the specific squid in the cephalopod family, which consists of "squid, octopus, cuttlefish and nautilus," other species do partake in ingesting sperm. The behavior has been seen in carrion flies, and picture wing flies, a marine nudibrach.
The squid does have a reason for the strange behavior; the sperm has a high nutrition content which helps with the growth of the female's eggs.
Apparently smaller females ingest sperm more often than larger ones. Male squid usually prefer to mate with larger females, which could be because they want to minimize the amount of sperm consumed and make it more likely for the egg to get fertilized, according to a press release.
"These squid live for just a year and have only a single breeding season before they die, so it's not surprising that the males can be highly strategic when evaluating potential mates," said Benjamin Wegener, PhD student at Monash University's School of Biological Sciences. "The findings suggest that males who copulate with smaller females could pay a higher price for their ejaculate expenditure."
The female squid stores sperm inside of a pocket below her mouth for fertilizing eggs at a later time. The study showed males were more likely to transfer the sperm to squids already carrying eggs.
"Interestingly, sperm storage appears to last only about three weeks in this species," Wegener said. "If females do not lay eggs within this timeframe, they still gain the nutrients from males through spermatophore consumption.
"It also raises more questions yet to be explored--are females using males as a food source or as a means to assess the quality of her partners? Are males even capable of using this feeding behavior to manipulate female reproduction? Hopefully future discoveries will uncover the answers," he said.
