Coelacanths have remained almost unchanged for 420m years.
Photograph: Alamy Stock PhotoBright blue,
Older than dinosaurs and weighing as much as an average-sized man, coelacanths are the most endangered fish in South Africa and among the rarest in the world.
Barely 30 of these critically-endangered fish are known to exist off the east coast of South Africa, raising concern that a new oil exploration venture in the area could jeopardise their future.
Coelacanths, whose shape has remained almost unchanged for 420m years, captured world attention when the first living specimen was caught off the port city of East London in 1938.
This discovery was followed by the subsequent capture of several more off the Comoros islands in the early 1950s, confirming that coelacanths were definitely not extinct.Shelf Life:
”The Sodwana coelacanths are about 40km from the northern boundary of the Eni exploration area and nearly 200km north of the first drilling sites, but Venter said oil spills spread far and swiftly.His concerns have been echoed by the coelacanth expert Prof Mike Bruton, who said the fish are specialist creatures, sensitive to environmental disturbance.
Photograph: Simon Maina/AFP/Getty Images
“Anything that interferes with their ability to absorb oxygen, such as oil pollution, would threaten their survival. The risk of oil spills or blowouts during exploration or futur is a source of serious concern.”
Bangkok-based photographer Visarute Angkatavanich (previously) continues to capture some of the most elegant portraits of fish we’ve seen.
His intimate, crystal-clear photos of Siamese fighting fish (betta) make it seem as though they are suspended in air instead of water.
Angkatavanich recently told Popular Photography that he only started photographing the fish after encountering them for the first time three years ago at a fish show and has since become obsessed with the different species which vary greatly in size, shape, and color patterns.
Limited edition prints of his work are now available through La Lanta Fine Art.
Fins with transparent membranes give the ribbonfish its name. Image Credit: Joshua Lambus.
Up to 2m long the ribbonfish is an elegant deep-sea creature.
Named for the elaborate fins that ripple delicately after them as they swim, ribbonfish from the genus Trachipterus are found all over the world.
There are six known species, and Australia’s is the southern ribbonfish, a 2m-long silvery creature with black polka dots on its sides and bright red fins.
Found off the coast of southern Queensland and South Australia, the southern ribbonfish has also set up a population off the coast of South Africa.
This fish is pretty much a taxonomic nightmare, because while it’s certainly a single species, according to the Australian Museum no one can decide whether its correct scientific name is T. jacksonensis or T. arawatae.
Eyes of the peacock mantis shrimp. The black bands show where it’s looking. Credit: Mike Bok
by Ed Yong
Eyes are testaments to evolution’s creativity. They all do the same basic things—detect light, and convert it into electrical signals—but in such a wondrous variety of ways.
There are single and compound eyes, bifocal lenses and rocky ones, mirrors and optic fibres. And there are eyes that are so alien, so constantly surprising, that after decades of research, scientists have only just about figured out how they work, let alone why they evolved that way.
To find them, you need to go for a swim.
This is the eye of a mantis shrimp—an marine animal that’s neither a mantis nor a shrimp, but a close relative of crabs and lobsters. It’s a compound eye, made of thousands of small units that each detects light independently.
Those in the midband—the central stripe you can see in the photo—are special. They’re the ones that let the animal see colour.
The rock mantis shrimp. Credit: Mike Bok.
Most people have three types of light-detecting cells, or photoreceptors, which are sensitive to red, green and blue light. But the mantis shrimp has anywhere from 12 to 16 different photoreceptors in its midband.
Most people assume that they must therefore be really good at seeing a wide range of colours—a “thermonuclear bomb of light and beauty”, as the Oatmeal put it. But last year,
Hanna Thoen from the University of Queensland found that they’re much worse at discriminating between colours than most other animals! They seem to use their dozen-plus receptors to recognise colours in a unique way that’s very different to other animals but oddly similar to some satellites.
Thoen focused on the receptors that detect colours from red to violet—the same rainbow we can see.
But these ultra-violent animals can also see ultraviolet (UV).
The rock mantis shrimp, for example, has six photoreceptors dedicated to this part of the spectrum, each one tuned to a different wavelength. That’s the most complex UV-detecting system found in nature.