London, June 24 (ANI): Some dads express their love by spending time with their children, but in case of some fish affection takes a whole new meaning.
Male sand gobies value their offspring so much that they devour them before a predator gets the chance, researchers have found.
According to Ashley Chin-Baarstad, a biologist at Purdue University in West Lafayette, Indiana, who led the new study, the "filial cannibalism" makes perfect sense for such animals because they invest time and energy in raising large numbers of offspring.
Male sand gobies tend the eggs from multiple females. But a long summer breeding season gives the males ample time to raise multiple broods and, rather than waiting until the eggs have hatched, sometimes they simply make a snack of them, reports New Scientist.
"They've decided it's just not worth it right now and for whatever reason they want to leave," Baarstad says.
In a bid to determine in what circumstances sand gobies decide to eat their offspring, the researchers mated dozens of males and females in outdoor tanks that mimicked conditions in the wild.
Males kept close guard on their hundreds of eggs, all buried safely in the sand.
However, when the researchers introduced an egg predator - the brown shrimp - into the tank, male gobies generally wolfed down their offspring and headed straight for the back of the tank.
Introducing the shrimp within plastic containers let the researchers restrict exposure to the egg eaters.
They found the gobies' cannibalistic tendencies increased at the sight and smell of the shrimp. A plastic container alone did not make dads turn cannibal, the study found.
The study has been published in the journal Animal Behaviour. (ANI)