CD 157: Investigating the submarine canyons off Portugal


My favourite marine animals

Many of you have been asking the team what their favourite marine animals are, so Dan (the one and only biologist on board the ship) took time out to write about his favourites...

My favourite marine animals are the cephalopods. This group includes squid, octopus, cuttlefish and nautiloids, and is where the ancient ammonoids and belemnoids once were placed. The cephalopods come in a diverse range of forms; from the sleek oceanic squids, adapted to a fast paced predatory lifestyle in the open ocean, to the octopus, which hides away in little cracks and holes on the seafloor, only coming out at night to hunt. These creatures have the amazing ability to change their colour and shape to match the surroundings, as a complex signalling behaviour and sometimes to reflect their mood.

Some ocean going squids are amongst the fastest marine creatures reaching speeds of up to 40kmph using directional jets of water to propel themselves. They have huge nerves, much larger than those of humans, an adaptation to their fast paced lifestyle, allowing their brains to react very quickly to their environment, making them efficient predators. Along with the cuttlefish and octopuses they have complex courting behaviour with a range of patterns and shapes they display to prospective partners to try and attract them - much better than the typical human efforts on a Friday night in Southampton!

The octopus is known for its problem solving ability and has often been called the 'most intelligent invertebrate', it has been known to develop 'relationships' with aquarists even using its water jets to squirt at them in a playful manner! Its hard body parts have been reduced to just the jaws so it can squeeze its way into the narrowest gaps with its muscular body, making it well suited to its habitat. They can be cunning escape artists in captivity using the smallest gaps in their tanks to escape, especially when there is a tank of tasty crabs nearby to raid!

Although I was asked to choose one favourite marine animal, I think the whole group are great in their own way. If you want any more information on these creatures check out

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April 2004
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