New shrew species discovery in Indonesia


This 2017 video is called Ferocious Shrews Fight For Mating Rights | Life Of Mammals | BBC Earth.

From Louisiana State University in the USA:

The naming of the shrew

Researchers discover the Sulawesi hairy-tailed shrew

March 11, 2020

Researchers at Louisiana State University have discovered a new species of shrew, which they have named the hairy-tailed shrew, or Crocidura caudipilosa.

“There was no doubt that this was a new species,” said LSU Museum of Natural Science Mammal Curator Jake Esselstyn whose work on Sulawesi Island in Indonesia led to the discovery published in the Journal of Mammalogy. “There isn’t another species on the island that has as much hair on its tail, in terms of shrews.”

The newly discovered shrew is slender with gray-brown fur on its back and silver-gray fur on its belly. Its tail is slightly longer than the combined length of its head and body and is covered with long bristles and hair, which make the distinctive tail very hirsute. In fact, no other shrew species in Indonesia, Malaysia or the Philippines is known to have such thick, long hair on its tail; however, some shrew species in Africa have very hairy tails. The scientists were also surprised to discover that this shrew climbs trees whereas most shrews live primarily on the ground, as far as anyone knows.

The Sulawesi hairy-tailed shrew was found on nine mountains across Sulawesi at various elevations from 1,500 feet to 4,800 feet.

“Tropical diversity is still not well documented even for mammals with a wide distribution on this island. This discovery shows how little we still know about mammal diversity,” Esselstyn said.

Puzzling pieces

The real challenge was figuring out which shrew is its closest relative and how this new species fits into the shrew family tree. Shrews‘ features do not change very much over time, which means closely related species tend to look very similar and are hard to distinguish from each other. This has posed a challenge for mammalogists in the past to discover new shrew species.

“Genetic data have revolutionized what we can distinguish between shrews. A lot of species are first recognized as being genetically distinct, then we look at its morphology, or physical features,” Esselstyn said.

Deforestation and degradation of natural habitats have also posed a challenge for discovering new species. For example, a few shrew specimens were collected in the early 20th century, but when scientists return to the same location where the early specimens were collected, the habitat is no longer a forest. It is a farm.

Despite these challenges, Esselstyn and his colleagues and students have also discovered several new mammals in Indonesia including the hog-nosed rat, the Sulawesi water rat and the slender root rat as well as the sky island moss shrew in the Philippines.

Meanwhile, at the LSU Museum of Natural Science, they continue to search and analyze specimens for more new species and to help put the pieces of the large tree of life puzzle together.

Hummingbird sized dinosaur discovery in amber


This 11 March 2020 video says about itself:

A tiny new species of bird-like dinosaur has been discovered, preserved in a lump of 99-million-year-old amber. The tooth-filled skull is only 7.1mm long, suggesting that this ancient creature would have been the size of a hummingbird – far smaller than other dinosaurs known from that time. Unusual features include large, side-facing eyes and a large number of sharp teeth suggesting a predatory lifestyle. The species has been named Oculudentavis khaungraae and is evidence of previously unimagined biodiversity in the Mesozoic era.

By Michael Greshko in National Geographic:

March 11, 2020

A spectacular new amber fossil from Myanmar holds the skull of the smallest prehistoric dinosaur ever found: a bird-like creature that lived 99 million years ago and grew no bigger than the smallest birds alive today.

The fossil, described today in the journal Nature, measures just 1.5 centimeters long from the back of the head to the tip of the snout, about the width of a thumbnail. The skull’s proportions suggest that the animal was about the same size as a bee hummingbird, which would have made the newfound dinosaur lighter than a dime.

The tiny creature appears to be most closely related to the feathered dinosaurs Archaeopteryx and Jeholornis, distant cousins of modern birds. Researchers suspect that like those animals, the small dinosaur had feathery wings, but without more fossils, they can’t determine how well it flew. And despite its hummingbird-like proportions, the tiny dinosaur was no nectar feeder. Its upper jaw bristled with 40 sharp teeth, and its huge eyes—suited for spotting prey in the foliage—have features unlike any seen in other dinosaurs. Fittingly, the creature’s genus name is Oculudentavis, derived from the Latin words for eye, tooth, and bird.

Pentagon covering up US soldiers with coronavirus


This 10 March 2020 video from the USA says about itself:

Is The US Military Hiding Its Coronavirus Cases?

A military mom calls in with devastating news, her son stationed in Afghanistan is sick, but the military either won’t test or isn’t testing the troops for Covid-19.

What is at the bottom of the lack of testing for members of the military, are we keeping the United States military safe enough to keep America safe?

Ancient rangeomorph animal networks, new research


This 7 March 2020 video says about itself:

Rangeomorphs had no mouths, guts, arms, legs or reproductive organs, but an ancient “network” of strings may have helped them dominate the ocean floor anyway.

Some of the earliest animals on Earth may have used social networks to chat with each other, review food — and yes — maybe even sext.

In a study published Thursday (March 5) in the journal Current Biology, researchers looked at hundreds of rangeomorphs — bizarre, fern-like animals that lived in large colonies on the bottom of the ocean from about 571 million to 541 million years ago — fossilized along the coast of Newfoundland, Canada. To the team’s surprise, many of the fossil specimens appeared to be connected to each other by long, string-like filaments never seen among animals this old. Individual filaments spanned anywhere from a few inches to 13 feet in length and connected rangeomorphs from seven different species, forming a primitive “social network” of deep-sea dwellers.

These organisms seem to have been able to quickly colonize the seafloor, and we often see one dominant species on these fossil beds. These filaments may explain how they were able to do that.

Rangeomorphs are thought to be some of the earliest non-microscopic animals on Earth, spreading prolifically 635 million to 541 million years ago, despite having no noticeable mouths, guts, reproductive organs or means of moving around.

Scientists think the creatures dug into the mud on the ocean floor, passively sucking nutrients out of the water using symmetrical, leaf-like branches. Their methods worked well, apparently, as rangeomorph colonies dominated huge plots of the seafloor for 30 million years. Different species ranged from less than 1 inch to 6.5 feet in length, and some may have physically changed shape to better capitalize on the nutrients available around them.

Because rangeomorphs never really moved around, the fossil record includes entire colonies of the creatures preserved as they actually lived. When professor at the University of Cambridge’s Department of Earth Sciences Alexander Liu and his colleagues found fossilized filaments connecting rangeomorphs at 38 different dig sites, it became clear that this sinewy “network” played an important role in connecting individual colony members.

Further study of rangeomorph fossils is required to unravel the mystery of these filaments; alas, it seems this social network is password-protected.

See here. And here.

North American birds biodiversity, new research


This 2017 video says about itself:

The National Geographic Guide to Birding in North America | The Great Courses

Look into six categories of bird behavior, as they provide vital information for identification. See how individual species are distinguished by typical or unique behavioral traits. Study the distinctive feeding habits of many species, and how we can recognize species from flight and flocking behavior. End by exploring the extraordinary mating and nesting customs of North American birds.

From Washington University in St. Louis in the USA:

Birds of a feather better not together

‘Homogenization’ threatens ecosystems at larger geographic scales

March 4, 2020

Diversity plays a key role in maintaining the stability of plant and animal life in an area. But it’s difficult to scale up smaller experiments to understand how changes will impact larger ecosystems.

A new study of North American birds from Washington University in St. Louis finds that the regional stability of ecosystems over time depends on both the total number of species present in a locality and on the variation in species identities among localities.

The results have implications for maintaining a diverse portfolio of local species in the face of major environmental threats — like climate change, biological invasions, intensifying land use and other human and natural disturbances. “Homogenization” may threaten ecosystems at larger geographic scales, the research suggests. The study is published March 4 in the Proceedings of the Royal Society B.

“Species diversity is changing in more complicated ways than just going up or down, or the total number of species,” said lead author Christopher P. Catano, a recent PhD graduate of Washington University and current postdoctoral research associate at Michigan State University. “One of the most critical and conspicuous ways that diversity is changing is by changing the distribution of species across space.”

Recent high-profile studies have tried to show how and why biodiversity is changing at regional to global scales. Scientists have sounded alarms about net losses of insect, fish, bird and plant species. Many fear that such losses may alter the functioning of ecosystems and upend their ability to provide critical goods and services that humans rely on.

“The study provides some of the first evidence to suggest that local biodiversity loss and biotic homogenization will impact the functioning and stability of ecosystems at macroscales,” said Jonathan Myers, associate professor of biology in Arts & Sciences.

A diverse portfolio — of birds

The greater the number of species in an ecosystem, the more that ecosystem tends to be stable. The general reason why this happens is something called an insurance effect.

In concept, it’s similar to why investors might want to have a diverse set of stocks in their portfolio. If one stock performs poorly, there’s a chance that it will be buffered by others that perform better than expected.

“Over time, these different stocks — or these different species, in the context of an ecosystem — can compensate for one another,” Catano said. “The fact that species may respond differently to the same environmental change is what gives that insurance effect.”

This idea is widely accepted by biologists. The basic mechanism has been confirmed by lots of studies over time, and it underlies many arguments to promote or conserve biodiversity.

But it’s not without its limitations. For example, much of the supporting research was conducted at a relatively small scale. One notable experiment was completed on plots of land that measured only about half as long as a bowling alley, each neatly planted with varying numbers and species of seeds.

Real life is not so clean. The ground is not perfectly flat, rivers cut through breeding areas, and animals and seeds travel across large areas. Ecosystem management often occurs within and across large tracts of land.

“At larger scales, it’s not just the number of species that’s potentially varying, it’s also the identity or the composition of those species across space,” Catano said.

“So there are two components to regional stability,” Catano said. “One is how stable your average local community is. And the second is how differently those local communities respond through time — relative to each other.”

Observations at a larger geographic scale

Catano and Myers decided to try to test the relative importance of these two factors — the number of species, and the amount of site-to-site variation in species composition — in determining the stability of ecosystems at a larger scale.

The researchers used 20 years of observational data from the North American Breeding Bird Survey, a joint effort of the U.S. Geological Survey and Environment Canada. They focused on 342 species of songbirds in 1,675 breeding bird “communities” — the census-block-like geographic units routinely sampled in the Breeding Bird Survey — distributed across 35 large bird-conservation regions.

The researchers used the production of total bird biomass over time as their measure of ecosystem stability.

They found that species count does matter for stability — but site-to-site variation in species composition matters three times as much at the larger geographic scale of bird conservation regions.

And what happens at a larger scale with birds is likely to affect humans, too. “Birds are major consumers of insect pests that limit production of plants and therefore ecosystems. Also, a lot of plants are dependent on seed dispersal by birds,” Catano said. “There’s a lot of critical services that are mediated by birds.”

A landscape that supports variation

The results have implications for conservation, the researchers said.

Land use managers have a key role to play in promoting variation across an area, the researchers said, by taking advantage of management techniques that introduce or maintain environmental heterogeneity.

“An example might be through grazing,” Catano said. “Animals graze somewhat patchily, and those patches create meaningful variation in the composition of other species. Fire management, or controlled burns, is another measure that, when done appropriately, can increase the resource heterogeneity in an ecosystem.

“These are things that land managers and conservation practitioners are already doing,” he added. “This just cues them into this other dimension of biodiversity that’s often overlooked when they assess the success of their restoration or management effort.

“Changes that lead to something like biotic homogenization could be destabilizing for ecosystems, even if it doesn’t lead to the loss of species.”