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Tangled love life of octopus

   A male octopus's hectocotylus, or mating arm (with pink lining), is inserted into the female's mantle.

 

 They flirt, hold hands and guard their lovers jealously - yet they don't even have bones.

 

The love lives of octopuses are far more complex than anyone thought, a team at the University of California, Berkeley, reported.

 

Researchers snorkeled off Indonesia to watch Abdopus aculeatus, an octopus with a spiky tan body the size of a small orange and arms 20cm to 25cm long.

 

Male cephalopods were seen guarding the dens of their mates for several days, warding off rivals and even strangling them if they got too close. Small males would sneak in to mate by swimming low to the ground in feminine fashion and not displaying their "male" brown stripes, the researchers reported in the journal Marine Biology.

 

 

The animals usually mate several times a day once they reach sexual maturity. Males have a specially designed arm they use to deposit a sperm packet into the female, who retires to her den and lays tens of thousands of eggs. Both parents die within a few months of mating, leaving the newborns to fend for themselves

 

Octopus Sex More Sophisticated Than Arm-wrestling

 For decades, scientists have viewed octopuses as unromantic loners, with mating habits nearly devoid of complex behavior. But new research from the University of California, Berkeley, has found that at least one species of octopus engages in such sophisticated lovemaking tactics as flirting, passionate handholding and keeping rivals at arms' length.

 

 biologists witnessed an array of complex mating behaviors as they snorkeled two meters or less above the shallow reefs of northern Sulawesi in Indonesia. For several weeks, they tracked Octopus Abdopus aculeatus, a diurnal species of cephalopod that typically sports a spiky tan body the size of a small orange and 8-to-10-inch-long sucker-lined arms.

 

In the wild, researchers observed macho octopuses that didn't just mate with the first female that crossed their path. Many picked out a specific sex partner and jealously guarded her den for several days, warding off rivals to the point of strangling them if they got too close. When flirting or fighting, they would signal their manliness by displaying striped body patterns.

 

 

Researchers also saw small "sneaker" males that moved in on unsuspecting conquests by masquerading as females. They did this by swimming low to the ground in feminine fashion and not displaying their "male" brown stripe. Plus, for the males, size really mattered: "If you're going to spend time guarding a female, you want to go for the biggest female you can find because she's going to produce more eggs "It's basically an investment strategy."

 

There are nearly 300 species of octopus in the world, ranging from the giant octopus in the Pacific Ocean to the tiny Octopus wolfi in the tropics. Mating is literally an octopus's life's work and can take place several times a day once the animal reaches sexual maturity. It usually begins with the male octopus poking the female with his long, flexible, hectocotylus arm and then slipping it into her mantle cavity.

 

Once the sperm packet has been deposited, the female retires to her den and lays tens of thousands of eggs, which she weaves into strings and attaches to the roof of her underwater dwelling. She keeps the eggs clean by blowing jets of water on them and is unable to leave her den to forage for food during this time. After about a month, the eggs hatch and the weakened mother octopus dies. The father also dies within a few months of mating, leaving the newborns to fend for themselves.

 

"It's not the sex that leads to death, Huffard said. It's just that octopuses produce offspring once during a very short lifespan of a year. And as the research team discovered, that once-in-a-lifetime lovemaking session is much more than just arm wrestling.

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