Mad as a Marine Biologist

High-res Yellow Tube Sponge Aplysina fistularis © moralcoral The few species of demosponge that have entirely soft fibrous skeletons with no hard elements have been used by humans over thousands of years for several purposes, including as padding and as cleaning tools. By the 1950s, though, these had been overfished so heavily that the industry almost collapsed, and most sponge-like materials are now synthetic. Sponges and their microscopic endosymbionts are now being researched as possible sources of medicines for treating a wide range of diseases. Dolphins have been observed using sponges as tools while foraging.

Yellow Tube Sponge

Aplysina fistularis

© moralcoral

The few species of demosponge that have entirely soft fibrous skeletons with no hard elements have been used by humans over thousands of years for several purposes, including as padding and as cleaning tools.

By the 1950s, though, these had been overfished so heavily that the industry almost collapsed, and most sponge-like materials are now synthetic.

Sponges and their microscopic endosymbionts are now being researched as possible sources of medicines for treating a wide range of diseases. Dolphins have been observed using sponges as tools while foraging.

High-res Lantern Bug [Pyrops sp] by Rich Cottrell “Pyrops is a genus of lantern fly that occurs primarily in southeast Asia, containing some 30 species. They are fairly large insects, with much of the length due to an elongated, upcurving, snout-like projection of the head. The wings are generally brightly patterned in contrasting colors, and they are popular among collectors.” - Wiki Do we have to collect everything?

Lantern Bug [Pyrops sp] by Rich Cottrell

“Pyrops is a genus of lantern fly that occurs primarily in southeast Asia, containing some 30 species. They are fairly large insects, with much of the length due to an elongated, upcurving, snout-like projection of the head. The wings are generally brightly patterned in contrasting colors, and they are popular among collectors.” - Wiki

Do we have to collect everything?

High-res ‘Just hanging out’ - Orang Utan Crab (Achaeus japonicus). Maybe, my favourite crustacean ever. Camouflaged to look like red algae, and so easy to miss, it is well sought after by divers with a penchant for the macro life. Often seen on bubble coral, I’ve only ever spotted one on my own once. When I tried to point it out to my dive buddies [both seasoned divers and marine biologists], I was gutted when they shrugged their shoulders and finned on. Surely they can’t be that seasoned? Upon surfacing, the conversation ended with simultaneous exclamations: “WHAT?! THAT WAS AN ORANG UTAN CRAB?? I thought you were just point out wierd algae”.

‘Just hanging out’ - Orang Utan Crab (Achaeus japonicus).

Maybe, my favourite crustacean ever. Camouflaged to look like red algae, and so easy to miss, it is well sought after by divers with a penchant for the macro life.

Often seen on bubble coral, I’ve only ever spotted one on my own once. When I tried to point it out to my dive buddies [both seasoned divers and marine biologists], I was gutted when they shrugged their shoulders and finned on. Surely they can’t be that seasoned?

Upon surfacing, the conversation ended with simultaneous exclamations:

“WHAT?! THAT WAS AN ORANG UTAN CRAB?? I thought you were just point out wierd algae”.

High-res Sea urchins use their entire body as an eye: For decades, scientists knew that sea urchins can respond to light, even though they don’t have anything that looks remotely like an eye. The mystery deepened in 2006, when the full genome of the purple sea urchin was published. To everyone’s surprise, its 23,000 genes included several that are associated with eyes. The urchin has its own version of the master gene Pax6, which governs the development of animal eyes from humans to flies. It also has six genes for light-sensitive proteins called opsins. While these genes are usually switched on in the developing eye, Maria Arnone found that the sea urchin’s versions are strongly activated in its feet. Sea urchins have hundreds of “tube feet”, small cylinders that sway around amid the spines. They can use the feet to move around, to manipulate food, and apparently to see. Esther Ullrich-Luter – one of Arnone’s collaborators – found that each foot has two clusters of light-sensitive cells: one at the tip and another at its base. Each foot has up to 140 of these cells, giving a total of 200,000 across the entire animal. (For comparison, humans have a thousand times as many.) The light-sensitive cells connect to a single nerve running down the length of each foot. The nerves of the tube feet eventually cluster into five spokes, which meet at a central ring of nerves. This is the extent of the urchin’s nervous system – it’s a sparse network of nerves without any central brain. Through this network, the sea urchin detects can react to light, which it spots with its hundreds of feet. Its entire surface is effectively a big compound eye. Read original article. Read paper. 

Sea urchins use their entire body as an eye:

For decades, scientists knew that sea urchins can respond to light, even though they don’t have anything that looks remotely like an eye. The mystery deepened in 2006, when the full genome of the purple sea urchin was published. To everyone’s surprise, its 23,000 genes included several that are associated with eyes. The urchin has its own version of the master gene Pax6, which governs the development of animal eyes from humans to flies. It also has six genes for light-sensitive proteins called opsins.

While these genes are usually switched on in the developing eye, Maria Arnone found that the sea urchin’s versions are strongly activated in its feet. Sea urchins have hundreds of “tube feet”, small cylinders that sway around amid the spines. They can use the feet to move around, to manipulate food, and apparently to see.

Esther Ullrich-Luter – one of Arnone’s collaborators – found that each foot has two clusters of light-sensitive cells: one at the tip and another at its base. Each foot has up to 140 of these cells, giving a total of 200,000 across the entire animal. (For comparison, humans have a thousand times as many.)

The light-sensitive cells connect to a single nerve running down the length of each foot. The nerves of the tube feet eventually cluster into five spokes, which meet at a central ring of nerves. This is the extent of the urchin’s nervous system – it’s a sparse network of nerves without any central brain. Through this network, the sea urchin detects can react to light, which it spots with its hundreds of feet. Its entire surface is effectively a big compound eye.

Read original article.

Read paper.