Sex for cephalopods

Ivory Towers
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The Independent Online
Until the late 1950s, little was understood about the thinking processes of the octopus. It was known that the octopus brain is not in two neat halves like our own, but is divided into quarters. Beginning with the seminal paper "Visual discrimination by octopus" in 1957, the psychologist N S Sunderland showed that this has profound effects on the way an octopus perceives the world. His later papers, "Visual discrimination of orientation and shape by octopus", "Visual discrimination of shape by octopus: squares and triangles", "Visual discrimination of the orientation of rectangles by octopus" and "Visual discrimination of shape by octopus: circles and squares, and circles and triangles" added to our knowledge. In particular, they showed that octopuses (or octopodes, but not octopi) can tell up from down, but not left from right. They also learn to recognise an object more quickly if they are taught to attack it rather than if they are only required to point.

Our fascination with the octopus was investigated by Federico de Luca Comandini in a 1989 paper entitled "Octopus: Metamorfosi di un'immagine animale" in which he pointed out that the animal's "alien form and uncanny intelligence has appealed to humankind's sense of mystery since prehistoric times." Only recently has our dread of its tentacles replaced the old sense of wonder.

In "Love American Style: II. `Octopoid' genitality and the medusal madonna", (Journal of Psychohistory, 1983) Kenneth Adams contends that "the biological and behaviour patterns of the octopus are well suited for the illustration of ontogenetic development and related fantasies". But what about the octopuses' own social lives?

Their interaction with fish has been well studied, with Jennifer A Mather ("Interactions of juvenile Octopus vulgaris with scavenging and territorial fishes") showing in 1992 that most encounters are with three types of fish: slippery dicks, dusky damselfish and hairy blennies. Although they generally retreat when attacked by damselfish, there is some argument over whether octopuses feel fear. They can, however, learn their way in mazes, and can remember things for at least 37 days. In 1992, ("Observational learning in Octopus vulgaris") it was shown that untrained octopuses can learn to imitate the behaviour of trained ones just by watching. In 1993, ("Personalities of octopuses, Octopus rubescens) it was shown that octopuses have personalities.

The sexual behaviour of the octopus is odd. "Nine captive females mated with two different males on consecutive days," John Cigliano reported in 1995. And it was the second male who mated longer. He concludes that "males were able to determine the mating history of females ... the increased length of these second matings may have occurred because males were removing or displacing previously deposited sperm from the female's oviduct." Further research is needed.