It is believed that the deepest-ever living fish has been found in the Japan Trench, Pacific.

A research team of British and Japanese scientist5s located and filmed the shoal of 17 fish on the bottom in 7.7km (4.8 miles) depth.

The 30cm-long, pale-coloured fish could be seen swimming about surprisingly energetically and eating shrimps.

The Hadeep research project began last year and has involved scientists from the University of Aberdeen’s Oceanlab and the University of Tokyo’s Ocean Research Institute. They have concentrated their lifeform studies on trench systems mainly around the Pacific Rim, at depths from 6-11km.

Funding has come from Britain’s Natural Environment Research Council and Japan’s Nippon Foundation. Research equipment has included custom-designed “landers”, highly pressure-resistant contraptions which have legs to stand on the seabed and, with lights and cameras at the ready, lie in wait for any passing creatures.

The newly discovered fish, named Pseudoliparis ambylstomopsis, is not the deepest ever located. That honour goes to the species Abyssobrotula galatheae which, in 1970, came up in a dredge from the bottom of the Puerto Rico Trench at a depth of 8km (5 miles). But it was dead by the time it was observed at the surface.

Genetic analysis has shown that a female shark gave birth to a pup made up entirely of her own DNA.
The American study, on an Atlantic blacktip shark housed in a Virginia aquarium, showed that the female had managed parthenogenesis - the ability to reproduce without having mated with a male.

The project team used DNA analysis similar to that used in human paternity testing. They were alerted to launch the study after the adult aquarium blacktip, called Tidbit, was found to be pregnant despite the fact that she had remained in captivity, with no contact with males, since shortly after her own birth in the wild.

This followed the discovery, in May last year, of parthenogenesis by a hammerhead aquarium shark in Omaha, Nebraska. More »