No need to brag.
Did it make a bit of difference to THIS human that you all have retained your sixth sense…
We we seem to have lost ours?
[via Physorg] People experience the world through five senses but sharks, paddlefishes and certain other aquatic vertebrates have a sixth sense: They can detect weak electrical fields in the water and use this information to detect prey, communicate and orient themselves.
A study in the Oct. 11 issue of Nature Communications that caps more than 25 years of work finds that the vast majority of vertebrates – some 30,000 species of land animals (including humans) and a roughly equal number of ray-finned fishes – descended from a common ancestor that had a well-developed electroreceptive system.
This ancestor was probably a predatory marine fish with good eyesight, jaws and teeth and a lateral line system for detecting water movements, visible as a stripe along the flank of most fishes. It lived around 500 million years ago. The vast majority of the approximately 65,000 living vertebrate species are its descendants.
“This study caps questions in developmental and evolutionary biology, popularly called ‘evo-devo,’ that I’ve been interested in for 35 years,” said Willy Bemis, Cornell professor of ecology and evolutionary biology and a senior author of the paper. Melinda Modrell, a neuroscientist at the University of Cambridge who did the molecular analysis, is the paper’s lead author.
Hundreds of millions of years ago, there was a major split in the evolutionary tree of vertebrates. One lineage led to the ray-finned fishes, or actinopterygians, and the other to lobe-finned fishes, or sarcopterygians; the latter gave rise to land vertebrates, Bemis explained. Some land vertebrates, including such salamanders as the Mexican axolotl, have electroreception and, until now, offered the best-studied model for early development of this sensory system. As part of changes related to terrestrial life, the lineage leading to reptiles, birds and mammals lost electrosense as well as the lateral line.
Some ray-finned fishes – including paddlefishes and sturgeons – retained these receptors in the skin of their heads. With as many as 70,000 electroreceptors in its paddle-shaped snout and skin of the head, the North American paddlefish has the most extensive electrosensory array of any living animal, Bemis said.
Until now, it was unclear whether these organs in different groups were evolutionarily and developmentally the same.
Using the Mexican axolotl as a model to represent the evolutionary lineage leading to land animals, and paddlefish as a model for the branch leading to ray-finned fishes, the researchers found that electrosensors develop in precisely the same pattern from the same embryonic tissue in the developing skin, confirming that this is an ancient sensory system.
The researchers also found that the electrosensory organs develop immediately adjacent to the lateral line, providing compelling evidence “that these two sensory systems share a common evolutionary heritage,” said Bemis.
Researchers can now build a picture of what the common ancestor of these two lineages looked like and better link the sensory worlds of living and fossil animals, Bemis said.
Makes a huge difference. I am horribly jealous.
Or rather I would be if weren’t for THIS bit of humorous news…
News that says despite these sharks super sixth sense to help them with ‘orientation’?
They got trapped on a golf course anyway.
In other words?
[via Sky News] Members of a golf club in Australia have something more to worry about than just their swing – playing on what’s thought to be the world’s first shark-infested course.Water hazards are a challenge for anyone who plays golf, but on the 14th tee at the Carbrook Golf Club in Brisbane there is another reason to be concerned.
Half a dozen man-eating bullsharks live in the lake in the centre of the course where their fins poking through the water have become a regular sight.
The sharks got onto the Queensland golf course when it flooded some years ago after a river broke its banks.
A golfer looks on as one of the man-eating bullsharks passes by
They became stranded when the water receded, but now they are thriving and even breeding.
“You can’t believe how close you are…just six feet away,” club general manager Scott Wagstaff said.
“There’s no drama, it’s become a positive thing for the golf course. They are amazing. I’ve become a shark lover since working here.”
There are six bullsharks now – but the number looks set to rise
Although the lake is well stocked with fish, Mr Wagstaff sometimes throws in meat to encourage the sharks to come near the surface.
“I’m sure they are aggressive when you are in the water but when you are out here feeding them they are beautiful to watch,” he told Sky News.
The sharks have become renowned in the region and there is even a monthly tournament called the “Shark Lake Challenge”.
Sign warning golfers not to venture into the lake
Golfers often pause during games for a few minutes to see if they can spot the sharks before they head off to the next tee.
The sharks, which are between 8 and 10ft long, have proved quite a hit at corporate events and their fins have even been spotted during wedding ceremonies held on the course.
Local children once jumped in the lake to retrieve lost golf balls for extra pocket money – but it is something they have not done for a while. [Read More]
Who is all super sixth-sensy now, huh sharks?
…Certainly NOT you.