Category Archives: science

Pacific blue-fin tuna

How warm-bodied tuna hearts keep pumping in killer cold

When tunas dive down to cold depths their body temperature stays warm but their heart temperature can fall by 15 degrees within minutes. The heart is chilled because it receives blood directly from the gills which mirrors water temperature. This clearly imposes stress upon the heart but it keeps beating, despite the temperature change. In most other animals the heart would stop.

Loggerhead Turtle, Caretta caretta

Loggerhead turtles home in on nests magnetically

Mother turtles find their way back to nesting beaches by looking for unique magnetic signatures along the coast, according to a new study published in Current Biology. Loggerhead turtles, for example, leave the beach where they were born as hatchlings and traverse entire ocean basins before returning to nest, at regular intervals, on the same stretch of […]

Crustacean

Sex-change crustaceans retain some masculinity

Male crustaceans avoid being completely feminised by pollutant-contaminated seawater as they “lock down” their maleness. New research by scientists at the University of Portsmouth has shown that crustaceans turned partially into females but retained a core of masculinity, and they may have learned how to do it after evolutionary battles with parasites. The research is […]

Helmut Jellyfish

Strange marine animals found around the Canary Islands

Marine conservation group Oceana finds amazing array of marine life in Canary Islands expedition, from shallows to down to 1000m. Using ROVs (remotely operated underwater vehicles) as well as scuba divers to shallow depths, they documented large colonies of deep-sea white coral, crystal aggregations of sponges, dense forests of black corals, oceanic puffers, giant foraminifera, carnivorous sponges and sharks, as well as many other biological communities and species in the south of the El Hierro Island.

SCUBA Fish Count

Silent divers count more fish

SCUBA divers underestimate the amount of life in heavily-fished areas, a study suggests. Scientists from Australia compared fish counts by SCUBA divers—who produce noisy bubbles—and divers using silent rebreathers. They found little difference in counts between the two in Marine Protected Areas (MPAs), where the fish weren’t frightened of the divers. In more heavily fished […]

Tiger Shark

Shark loss hits global ecosystems

The loss of sharks could contribute to the destruction of one of the planet’s most under-appreciated sources of carbon storage — seagrasses, according to FIU researchers. Not that sharks eat the seagrass, they don’t, but they do eat the turtles which feed in the seagrass meadows. Add this to the problems of pollution, mooring and […]