New research shows sea spiders use a unique mechanism to move oxygen through out their bodies. Most animals use their heart to move oxygen. Sea spiders use their guts.
"Unlike us, with our centrally located guts that are all confined to a single body cavity, the guts of sea spiders branch multiple times and sections of gut tube go down to the end of every leg," H. Arthur Woods, researcher at the University of Montana, Missoula, said in a news release. "In effect, sea spiders guts are 'space-filling' and ubiquitous in their bodies in the same way that our circulatory systems are space-filling and ubiquitous."
Sea spiders use gut peristalsis to move oxygen through their guts. The mechanism, the involuntary constriction and relaxation of gut muscles, is the same used by the guts of most animals to move matter through the digestive system.
The peristaltic waves generated by the sea spider's rapidly contracting gut muscles are much stronger than what would be sufficient for the movement of digested matter alone.
Sea spiders absorb oxygen directly through their cuticles, or hairs, that line their long, slender legs. The oxygen is then moved through the body by the gut's extra strong peristaltic waves.
The latest research — published this week in the journal Current Biology — is part of a broader effort to understand "polar gigantism" impacts various biological mechanisms. Species adapted to polar habitats tend to boast larger bodies their relative living closer to the equator.
Woods and his colleagues were curious to find out how animals like sea spiders move oxygen throughout such a large body.
Because the bodies of sea spiders are so skinny, it is easy to see inside with a microscope. Researchers noticed the hearts of sea spiders weren't moving blood beyond the center of the body.
"My 'aha!' moment was to consider that maybe all that sloshing of blood and guts was not about digestion but instead about moving respiratory gases around," Woods said.
Researchers used biomarkers and imaging to trace the movement of blood. They also manipulated spiders' gut peristalsis and measured the impact on the movement of oxygen.
Their findings confirmed their hypothesis that the spiders use their guts to transport oxygen. Researchers suggest analysis of arthropods with similarly complex gut systems could reveal unique respiratory mechanisms.
Malaysia foils bid to smuggle 'bearded dragons'
Kuala Lumpur (AFP) July 10, 2017 –
Malaysia has foiled an attempt to smuggle dozens of bearded dragon lizards and tortoises into the country from neighbouring Thailand to be sold as pets, authorities said Monday.
Two Thais and one Malaysian were arrested as they drove an SUV with the animals hidden inside, according to local border security chief Syed Basri Syed Ali.
Authorities found 58 bearded dragons and eight African spurred tortoises.
Both animals are popular pets in Malaysia but it is illegal to bring them into the country without the correct permits.
If found guilty of breaking wildlife protection laws, the trio — who were arrested Thursday — could be jailed for up to 10 years, said Syed Basri.
Kanitha Krishnasamy, acting regional director for wildlife trade monitoring network Traffic, told AFP the discovery could help investigators probing pet smuggling.
"This case could potentially uncover connections to the exotic pet trade that appears to be booming in Malaysia," she said.
African spurred tortoises are kept as pets due to their reputation for having a pleasant temperament. The world's third-largest tortoise, they are classified as "vulnerable" by protection group the International Union for Conservation of Nature.
Bearded dragons — which take their name from the scales under their head that resemble a beard — are popular pets due to their hardy and tame nature.
Birth of wolf cubs in Mexico raises hopes for endangered species
Mexican zoo officials are drooling over the birth of seven cubs of a species of endangered wolf.
They were born in April to a female named Pearl, who was nice and plump and ended up delighting vets with a surprisingly large litter.
"We were expecting four or five," Arturo Gayosso, director of the Zoologico los Coyotes in Mexico City, told AFP this week.
These are known as Mexican wol … read more
