Fossil invertebrates, new study


This vido says about itself:

12 January 2017

For 175 years, a cone-shaped, shelled prehistoric creature called a hyolith has been waiting to be assigned a proper place on the tree of life. Thanks to a recent research effort, the hyolith’s wait is over.

From Science News:

Ancient oddball invertebrate finds its place on the tree of life

by Cassie Martin

2:30pm, January 11, 2017

Hyoliths are evolutionary misfits no more.

This class of ancient marine invertebrates has now been firmly pegged as lophophorates, a group whose living members include horseshoe worms and lamp shells, concludes an analysis of more than 1,500 fossils, including preserved soft tissue.

The soft-bodied creatures, encased in conical shells, concealed U-shaped guts and rings of tentacles called lophophores that surrounded their mouths. Fossil analysis suggests that hyoliths used those tentacles and spines, called helens, to trawl the seafloor more than 500 million years ago, researchers report online January 11 in Nature.

For years, paleontologists have argued over where on the tree of life these bottom-feeders belonged. Some scientists thought hyoliths were closely related to mollusks, while others thought the odd-looking creatures deserved a branch all their own. This new insight into hyolith anatomy “settles a long-standing paleontological debate,” the researchers write.

Sea spider anatomy, new research


This video says about itself:

6 July 2015

Quick facts about these thin-legged arthropods! The Sea Spider (Pycnogonida/Pantopoda)! Sea Spider facts!

From Science News:

It takes guts for a sea spider to pump blood

These arthropods’ unusual digestive system can act like a heart and gills

By Susan Milius

4:46pm, January 11, 2017

NEW ORLEANS — A newfound way of delivering oxygen in animal circulatory systems depends mostly on food sloshing back and forth in the guts.

This discovery came in sea spiders, or pycnogonids, which can look like legs in search of a body. Their spookily long legs hold stretches of digestive tract, which wouldn’t fit inside the creatures’ scrap of an abdomen. Waves of contraction sweeping up and down the leggy guts cause blood outside the guts to move too, evolutionary physiologist Art Woods of the University of Montana in Missoula said January 8 at the annual meeting of the Society for Integrative and Comparative Biology. As lumpy surges of partly digested food rise and fall, blood that has picked up oxygen by diffusion whooshes to the rest of the body, Woods proposed.

“Essentially they use their legs like gills,” says Jon Harrison, an evolutionary physiologist at Arizona State University in Tempe, who was not involved in the research. “To my knowledge, no one had thought of this before — certainly no one has demonstrated this before.”

The roughly 1,300 sea spider species aren’t true spiders but a closely related lineage of arthropods. They feed via a long proboscis that doesn’t punch into food but gnaws at it bit by bit and then sucks up the smaller nuggets. Those nuggets typically come from hunting or scavenging other invertebrates. Jellyfish and hydroids are some sea spiders’ favorites with occasional other snacks such as clams or sea slugs. Various sea spider species live from the tropics to the poles, and in Antarctica, sea spiders grow to a leg span wider than a dinner plate.

Woods and colleagues were studying this polar gigantism when they began thinking through the spiders’ oxygen consumption. A sea spider’s outer covering is porous enough for oxygen to diffuse through. But the researchers calculated that mere diffusion without some kind of inner pump couldn’t meet these animals’ oxygen needs.

Most sea spider species have a heart and, like other arthropods, an open circulatory system. The heart shoots a pulse of blood out open-ended vessels where it washes over body tissues and then flows back into the heart’s uptake plumbing.

A sea spider heart might boost flow to such blood-hungry zones as the muscular proboscis, but the researchers didn’t see big, regular pulses of blood radiating outward through the body. Hearts probably aren’t the whole story for circulation, Woods concluded.

The researchers also observed that there’s more oxygen in the tips of the legs. Gut activity could then drive the newly oxygenated blood up the leg toward the rest of the body. A video showed a stretch of gut bulging wide inside the leg as a dollop of food washed through, shrinking as the wake died away and then swelling again as a food wave arrived from the opposite direction. These motions inside gut tissue let the oxygen-enriched blood circulate, Woods proposed.

To test the idea, the researchers lowered the oxygen content of water around sea spiders. The movements of the digestive tract increased, as expected if the guts had to work harder to supply oxygen. And when researchers raised the water temperature for both polar and temperate species, which revs up metabolism and increases oxygen demand, gut activity increased, too.

Woods proposes that sea spider blood circulation by gut motion might prove to be what paleontologist Stephen Jay Gould called an exaptation, a trait with one function that over the course of evolution takes on another. Woods’ guess: The digestive system formed first and later happened into circulation.

New Samoan beetle species discovered, already extinct


Holotype specimen of Bryanites graeffii. Image credit: J.K. Liebherr

From Sci News:

Bryanites graeffii: New Beetle Species Described from 150-Year-Old Museum Specimen

Jan 11, 2017 by News Staff

A new species of ground beetle has been identified by Cornell University Professor James Liebherr.

Bryanites graeffii is described from Samoa based on a single male specimen collected between 1862-1870 that was recently discovered in the Muséum national d’Histoire naturelle, Paris,” Prof. Liebherr said.

“The species epithet honors Dr. Eduard Graeffe, zoologist and naturalist from Zurich, Switzerland who collected the specimen while working in Samoa from 1862-1870. The species epithet is formed from Gräffe converted to Latin iconography, and without the terminal letter,” he explained.

The new species belongs to Bryanites, a genus of beetles in the family Carabidae that was previously known from two species represented by two specimens only, collected in 1924 from Savai’i Island, Samoa, by Edwin H. Bryan, Jr., Bernice P. Bishop Museum in Honolulu, during the Bishop Museum’s Whitney South Seas Expedition.

Much like the rest of the species within the genus, Bryanites graeffii showed vestigial flight wings and other traits associated with flight-wing loss.

However, at length of 1.62 cm it is the largest for the taxonomic group it is now assigned to.

Although this may seem way too obvious for taxonomists to overlook, the beetle’s relatives are just as obscure.

“As a result, we now have three species representing an evolutionary radiation in Samoa, all known from single specimens collected long ago,” Prof. Liebherr said.

The phylogenetics of the three Bryanites species link them to other groups from Fiji and New Zealand.

“What is the advantage of knowledge about species that existed some 90-150 years ago, but no longer? It might actually point us to the actual level of impact mankind has on natural ecosystems,” Prof. Liebherr said.

“The cause of the likely extermination of Bryanites graeffi might never be known with certainty, however, the colonization of many Pacific islands by the Polynesian rat has always been followed by the diminution or elimination of native insect species.”

“Thus, we can add another likely victim to the list of species that have been adversely impacted by mankind’s commensal voyagers.”

A detailed description of Bryanites graeffii appears in the Jan. 5 issue of the journal Zoosystematics and Evolution.

New ‘Star Wars’ ape species discovered in China


This video from India says about itself:

Conservation of the Eastern Hoolock Gibbon

6 June 2011

Now wouldn’t that call make just the perfect mobile ring tone?

In the jungles of Arunachal Pradesh‘s Mehao national park, Wilderness Films India sent a team to film the Hoolock Gibbon in its natural habitat.

The Hoolock gibbon or Uluk, belongs to the ape family. It is only found in the deciduous forests of China, Bangladesh, Myanmar and India. The average lifespan of these gibbons is thirty years in captivity. A male Hoolock Gibbon is recognized by his black fur and a white strip above his eyes while the female gibbon is recognized by her pale fur with shades of tan.

The gibbons move around by using their arms. They are mostly found in trees and rarely come onto the ground. Hoolock gibbons are primarily omnivorous and consume various types of plants, insects and birds’ eggs. The various activities of the gibbon during the day include feeding, resting, foraging, travelling with the rest of the troupe. They indulge in other activities such as calling for territorial behavior and play. Territories are defended through disputes usually led by the group’s adult male.

Intergroup encounters occur often and usually consist off vocalisation and counter vocalization with the males chasing one another. Grooming is often seen during the group’s social activities and it serves in the maintenance of social bonds. Mating usually occurs during the summer season with births during the winter.

Gestation occurs for around 6-8 months followed by the birth of an offspring. For the first two months, the infants cling on to their mother’s belly. The infant starts showing signs of independence at the age of 6-8 months. However, the bond is so strong between the mother and child that the infant continues to sleep with the mother until the birth of a new infant. The infants emigrate from their group when they become mature adults.

Out of all the gibbons, the Hoolocks have the most haunting call. The calls of these Gibbons are not sex-specific, a fact that differs them from all other species of gibbons. Calls are usually uttered during long call outs or duels and occur mainly in the morning. Once calling commences, call outs are often responded to by other hoolock gibbons throughout the forest. Functions of calling include the maintenance of the pair bond, mate attractions, defense, mate solicitation, territorial reinforcement and the maintenance of social ties.

Some of the proposed steps for conservation of the gibbons are: restoration of degraded landscapes, combining efforts made by the government industry, NGOs and communities in Northeast India. Increasing and nationalizing existing protected area network and protected area management. It is important to ensure the enforcement of these goals for the protection of this incredible species and to prevent them from disappearing from the surface of the earth.

This video was researched by Saurabh Bhatia of The Shri Ram School, Gurgaon, during a summer internship with WFIL, in May-June 2011.

From the BBC:

‘Star Wars gibbon’ is new primate species

By Rebecca Morelle, Science Correspondent, BBC News

4 hours ago

A gibbon living in the tropical forests of south west China is a new species of primate, scientists have concluded.

The animal has been studied for some time, but new research confirms it is different from all other gibbons.

It has been named the Skywalker hoolock gibbon – partly because the Chinese characters of its scientific name mean “Heaven’s movement” but also because the scientists are fans of Star Wars.

The study is published in the American Journal of Primatology.

Dr Sam Turvey, from the Zoological Society of London, who was part of the team studying the apes, told BBC News: “In this area, so many species have declined or gone extinct because of habitat loss, hunting and general human overpopulation.

“So it’s an absolute privilege to see something as special and as rare as a gibbon in a canopy in a Chinese rainforest, and especially when it turns out that the gibbons are actually a new species previously unrecognised by science.”

Hoolock gibbons are found in Bangladesh, India, China and Myanmar. They spend most of their time living in the treetops, swinging through the forests with their forelimbs, rarely spending any time on the ground.

But the research team – led by Fan Peng-Fei from Sun Yat-sen University in China – started to suspect that the animals they were studying in China’s Yunnan Province were unusual.

All hoolock gibbons have white eyebrows and some have white beards – but the Chinese primates’ markings differed in appearance.

Their songs, which they use to bond with other gibbons and to mark out their territory, also had an unusual ring.

So the team carried out a full physical and genetic comparison with other gibbons, which confirmed that the primates were indeed a different species.

They have been given the scientific name of Hoolock tianxing – but their common name is now the Skywalker hoolock gibbon, thanks to the scientists’ taste in films.

Dr Turvey said the team had been studying the animals in the Gaoligongshan nature reserve, but it was not easy.

“It’s difficult to get into the reserve. You have to hike up to above 2,500m to find the gibbons. That’s where the good quality forest usually starts – everywhere below there has been logged.

“Then you have to wake up really early in the morning and you listen out for the haunting song of the gibbons, which carries in the forest canopy.

“And when you hear it, you rush through the mud and the mist, and run for hundreds of metres to try and catch up with these gibbons.”

The researchers estimate that there are about 200 of the Skywalker gibbons living in China – and also some living in neighbouring Myanmar, although the population size there is currently unknown.

The team warns that the primates are at risk of extinction.

“The low number of surviving animals and the threat they face from habitat loss, habitat fragmentation and hunting means we think they should be classified as an endangered species,” said Dr Turvey.

In response to the news, actor Mark Hamill – the original Luke Skywalker – said on Twitter that he was so proud to have a new jungle Jedi named after his character.

Palm warblers eat insects from spiders’ webs


This video from the USA says about itself:

9 January 2017

Several Palm Warblers hunt for insects in spiders‘ webs in the morning – just like going to the grocery store! The spiders do all the hard work and the Warblers wisely reap some rewards. This behavior has apparently not been too well documented on video, although there is a technical name for this that I just learned – Kleptoparasitism (a form of feeding in which one animal takes prey or other food from another that has caught, collected, or otherwise prepared the food, including stored food). Always something new to learn by observing Nature!

Here is a link to a short scientific paper on the subject.

Three new flatworm species discovered in Brazil


This video says about itself:

Huge flatworm (Platyhelminthes) on the move

16 August 2009

We discovered this flatworm on one of our nightly walks in the jungle of Itatiaia National Park in Brazil.

From Phys.org:

Hidden diversity: 3 new species of land flatworms from the Brazilian Araucaria forest

January 9, 2017

A huge invertebrate diversity is hidden on the forest floor in areas of the Araucaria moist forest, Brazil. Land flatworms constitute a numerous group among these invertebrates occurring in the Neotropical region. Flatworms are considered to be top predators within the soil ecosystem, preying on other invertebrates.

The Araucaria moist forest is part of the Brazilian Atlantic Rain Forest and is considered a hotspot of land flatworm diversity, harboring many yet undescribed species. A study recently published in the open access journal ZooKeys describes three new species from areas covered by Araucaria moist forest in South Brazil, which belong to the Neotropical genus Cratera.

Land flatworms lack a water retention mechanism and have a low tolerance to intense changes in temperature and humidity. Their low vagility leads to the existence of a high number of endemic species. Thus, they are considered good bioindicators of the degree of impact on their habitat.

The new species are named after characteristics of their color pattern and are probably endemic for the study areas. Besides differing from each other, as well as from other species of the genus, by their characteristic color pattern, they also show other distinguishing features in the reproductive system. The study provides an identification key to the species of the genus.

The work was conducted by the south Brazilian research group on triclads, led by Dr. Ana Leal-Zanchet, of the Universidade do Vale do Rio dos Sinos (UNISINOS), in southern Brazil. The study was supported by the Brazilian Research Council (CNPq).

Flatworms in the Netherlands: here.

How hagfish survive shark attacks


This video says about itself:

Hagfish predatory behaviour and slime defence mechanism

26 October 2011

Hagfishes (Myxinidae) are a family of jawless marine pre-vertebrates. Those video images taken in New Zealand revealed that hagfishes are able to choke their would-be predators with gill-clogging slime.It also shows that hagfishes are actively preying on other fish in New Zealand waters.

The video is part of a scientific paper describing this newly discovered behaviour which can be downloaded online.

From Science News:

Unusually loose skin helps hagfish survive shark attacks

Slip-sliding outer covering also aids in Houdini escapes

By Susan Milius

6:26pm, January 6, 2017

NEW ORLEANS, La. – Skin that mostly hangs loose around hagfishes proves handy for living through a shark attack or wriggling through a crevice.

The skin on hagfishes’ long, sausage-style bodies is attached in a line down the center of their backs and in flexible connections where glands release slime, explained Douglas Fudge of Chapman University in Orange, Calif. This floating skin easily slip-slides in various directions. A shark tooth can puncture the skin but not stab into the muscle below. And a shark attack is just one of the crises when loose skin can help, Fudge reported January 5 at the annual meeting of the Society for Integrative and Comparative Biology.

Hagfishes can fend off an attacking shark by quick-releasing a cloud of slime. Yet video of such events shows that a shark can land a bite before getting slimed. To figure out how hagfishes might survive such wounds, Fudge and colleagues used an indoor guillotine to drop a large mako shark tooth into hagfish carcasses. With the skin in its naturally loose state, the tooth readily punched through skin but slipped away from stabbing into the body of either the Atlantic (Myxine glutinosa) or Pacific (Eptatretus stoutii) hagfish species.

But when the researchers glued the skin firmly to the hagfish muscle so the skin couldn’t slip, the tooth typically plunged into inner tissue. For comparison, the researchers tested lampreys, which are similarly tube-shaped but with skin well-fastened to their innards. When the guillotine dropped on them, the tooth often stabbed directly into flesh.

The finding makes sense to Theodore Uyeno of Valdosta State University in Georgia, whose laboratory work suggests how loose skin might work in minimizing damage from shark bites. He and colleagues have tested how hard it is to puncture swatches of skin from both the Atlantic and Pacific species. As is true for many other materials, punching through a swatch of hagfish skin held taut didn’t take as long as punching through skin patches allowed to go slack, he said in a January 5 presentation at the meeting. Even a slight delay when a sharp point bears down on baggy skin might allow the hagfish to start dodging and sliming.

But Michelle Graham, who studies locomotion in flying snakes at Virginia Tech, wondered if puncture wounds would be a drawback to such a defense. A hagfish that avoids a deep stab could still lose blood from the skin puncture. That’s true, said Fudge, but the loss doesn’t seem to be great. Hagfish have unusually low blood pressure, and video of real attacks doesn’t show great gushes.

Hagfish blood also plays a part in another benefit of loose skin — an unusual ability to wiggle through cracks, Fudge reported in a second talk at the meeting. One of his students built an adjustable crevice and found that both Atlantic and Pacific hagfishes can contort themselves through slits only half as wide as their original body diameter. Videos show skin bulging out to the rear as the strong pinch of the opening forces blood backward.

The cavity just under a hagfish’s skin can hold roughly a third of its blood. Forcing that reservoir backward can help shrink the body diameter. Fortunately the inner body tapers at the end, Fudge said. So as blood builds up, “they don’t explode.”