October 2012

Sharks possess brain-to-body mass ratios that are similar to mammals and birds and have exhibited apparent curiosity and behaviour resembling play in the wild

Shark brains similar to humans

The parallels are outlined in several papers published in a special edition of the journal Brain, Behavior and Evolution.

Though once thought to have empirically simple brains, cartilaginous fishes possess a battery of highly developed sensory systems, a complex range of innate behaviours, and relatively enlarged and complex brains, which, unlike many other vertebrate systems, continue to grow throughout life.

Animals mix the oceans

Biosphere mixing appears to provide about one third the power required to bring the deep, cold waters of the world ocean to the surface, which in turn completes the ocean's conveyor belt circulation critical to the global climate system.

Energy put into the oceans by small animals such as krill is a significant component of the total contributed by all swimming creatures, adding up to a force comparable to that of winds and tides.

(Filephoto) Bottlenose dolphin

Dolphins comprehend sentences

The ability of two bottlenosed dolphins Tursiops truncatus to understand imperative sentences expressed in artificial languages were studied. One dolphin (Phoenix) was tutored in an acoustic language whose words were computer-generated sounds presented through an underwater speaker. The second dolphin (Akeakamai) was tutored in a visually-based language whose words were gestures of a trainer's arms and hands.

Does this whale talk?

Excerpts from Current Biology, Volume 22, Issue 20, R860-R861, 23 October 2012

The whale lived among a group of dolphins and socialized with two female white whales. The whale was exposed to speech not only from humans at the surface -- it was present at times when divers used surface-to-diver communication equipment.

Bull shark.
Bull shark.

Bull sharks have strongest bite of any shark

Research has revealed that bull sharks bite with almost 6,000N, a force that is greater than what is required to kill and eat prey. In a study published in the journal Zoology, Maria Habegger from Tampa’s University of South Florida, along with colleagues in the US and Germany, examined bite forces produced by 13 shark species and their close relatives, ranging from 1m-long ratfish to the great white shark.

Mantas affected by moon

The research by Fabrice Jaine and colleagues identifies environmental factors that predict the abundance and behavior of manta rays at Lady Elliott Island in the Great Barrier Reef.

The authors comment that knowing these factors is important for conservation efforts, "especially in the context of a changing climate and with targeted fisheries increasingly threatening manta ray populations in various parts of the world."

California Sea Lion (Zalophus californianus) seen in Santa Cruz, California

How seals avoid the bends

Documentation of lung collapse and estimation of the depth at which collapse occurs has been difficult and only obtained in a few species.

Researchers led by Birgitte McDonald at the Scripps Institution of Oceanography netted a female adult California sea lion (Zalophus californianus), anaesthetised the animal and fitted it with loggers to record oxygen pressure in its main artery and the time and depths to which it dived.

Electron micrograph of Bacteriophages (vira) in the process of infecting a cell. This is not the virus or bacteriophage in question but a generic photo

A vaccine for corals

White syndrome' is a name given to a number of diseases exhibiting similar symptoms, such as such as white pox, white band and white plague disease. The causes of white syndrome are in many cases unknown. White syndrome has increased in abundance 20-fold in the last five years, with increases on inner, mid-shelf and outer-shelf reefs along the length of the Great Barrier Reef. It also had a major impact on Caribbean reefs. In areas of the Great Barrier Reef surveyed, white syndrome, along with skeletal eroding band, was the most common disease.