Buzzard, otter, beaver at camera trap


This 2016 camera trap video from Friesland province in the Netherlands shows a buzzard which has caught a water vole; a beaver and an otter.

Chipmunks in the USA, videos


This video from the USA says about itself:

1 October 2016

One Chipmunk devours an entire ear of dried corn at 10 times normal speed. The little rodent will brighten and energize your day – set to the upbeat “Glee Club Polka” you wont be able to resist tapping your foot. It took the little one 16 minutes to do it in real time – the full video is here.

This video from the USA says about itself:

6 October 2016

Young Chipmunk kitten out of the nest and on his own is learning how to stuff a huge peanut in his little mouth and get it into his cheek pouches. Late September and early October is the time the young squirrels and chipmunks are forging out on their own and learning what is good to eat and how to eat it. Because this little guy is so small stuffing his cheeks makes his head look entirely too big for hist little body!

Chipmunks and mice, why are they striped?


This video says about itself:

Place to take footage: Ramna Park, Dhaka, Bangladesh

Date: 03.07.2015

The palm squirrel or three-striped palm squirrel, Funambulus palmarum, is a species of rodent in the family Sciuridae found naturally in Bangladesh & India (south of the Vindhyas) and Sri Lanka. In the late 19th century, the palm squirrel was introduced into Western Australia, where it has since become a minor pest, actively targeted for eradication due to its lack of natural predators. The closely related five-striped palm squirrel, F. pennantii, is found in northern India, and its range partly overlaps with this species.

The palm squirrel is about the size of a large chipmunk, with a bushy tail slightly shorter than its body. The back is a grizzled, gray-brown color with three conspicuous white stripes which run from head to tail. The two outer stripes run from the forelegs to the hind legs only. It has a creamy-white belly and a tail covered with interspersed, long, black and white hair. The ears are small and triangular. Juvenile squirrels have significantly lighter coloration, which gets progressively darker as they age. Albinism is rare, but exists in this species.

From Science News:

Gene gives mice and chipmunks their pinstripes

Biologists identify new molecular pathway behind mammalian fur patterns

By Tina Hesman Saey

2:00pm, November 2, 2016

Chipmunks and other rodents’ light stripes are painted with a recycled brush, a new study suggests.

A protein previously known to guide facial development was repurposed at least twice during evolution to create light-colored stripes on rodents, researchers report November 2 in Nature. The protein, called ALX3, could be an important regulator of stripes in other mammals, including cats and raccoons, says Michael Levine, a developmental biologist at Princeton University who was not involved in the new study.

Some research has shown how butterflies and other insects create their often elaborate wing patterns (SN: 7/17/10, p. 28). But scientists still don’t understand the biological machinery used by mammals to generate the dots, spots, splotches and stripes that decorate their coats. Uncovering the molecular equipment may shed light on the evolutionary processes that help animals camouflage themselves and adapt to their environments.

In the new study, evolutionary developmental biologist Ricardo Mallarino of Harvard University and colleagues examined the multicolored stripes of African striped mice (Rhabdomys pumilio). Two light-colored stripes, each flanked by black stripes, run down the mice’s backs. A strip of fur the same brownish color as most of the rest of the body separates the dark-light-dark striping. The patterns are created by three types of hair: Hairs with banded yellow shafts growing from a black base populate the strip in the middle, while completely black hairs from base to tip are found in the black stripes. Hairs with a black base but no pigment in the shaft make up the light stripes.

Those unpigmented hairs were mysterious, says Hopi Hoekstra, the Harvard evolutionary biologist who led the new study. Usually, white hair arises because animals have a mutation that prevents cells from making pigments, she says. But since the African striped mice carry no such mutations, it was clear that the mice must create the stripes in a different way.

In vertebrates, pigment-producing cells called melanocytes migrate around the body as the embryo develops. One way stripes could form is by melanocytes moving to create the pattern. Previous research in zebrafish indicated that stripes on the fish’s sides form that way (SN: 2/22/14, p. 9). Light stripes might result if the melanocytes don’t migrate into a strip of the mice’s skin, the researchers reasoned. Hair would grow there, but wouldn’t have any pigment. That’s the first thing Mallarino checked. He examined white stripes in the skin of striped mouse embryos a couple of days before birth. Melanocytes had no trouble infiltrating the light striped area, he found. But once in the stripe, the cells did not mature properly and so made no pigment.

To find out what might be stopping melanocytes from producing pigment, the researchers examined gene activity in the different types of stripes in the mouse embryos. In the light stripes, the gene that produces ALX3 is much more active than it is in the brown or black stripes, the researchers discovered. That result was a surprise because no one knew that ALX3 is involved in pigmentation, Hoekstra says. It was known for helping to regulate the formation of bones and cartilage in the face.

It wasn’t clear whether the high levels of ALX3 caused the light stripes or not. So Hoekstra’s team did experiments in lab mouse cells to find out how the protein might affect pigmentation. Raising levels of ALX3 in cells interfered with activity of a gene called Mitf, a master regulator of pigment production and melanocyte maturation.

It turns out that even in lab mice more of the protein is made on the belly, which tends to be light colored. Previous pigmentation research failed to turn up ALX3 because researchers were working with white mice, Hoekstra says.

Eastern chipmunks (Tamias striatus), which last shared a common ancestor with African striped mice about 70 million years ago, also made more ALX3 in the light stripes on their flanks, the researchers found. The results suggest that different rodents independently recycled ALX3’s ability to make light-colored belly fur and used it to also paint light stripes on the back. Stripes may help rodents that are active during the day blend into the background and avoid the sharp eyes of predators, Hoekstra says.

Evolution tends to be thrifty, often reusing old genes for new purposes, says Nipam Patel, an evolutionary developmental biologist at the University of California, Berkeley. The new study is “a really nice illustration that evolution isn’t biased,” he says. “It takes what it gets and works with that.”

The researchers still don’t know why ALX3 gets turned up in the light stripes. Another protein may turn on its production, or rodents have found other ways to dial up ALX3 production in certain places. Researchers need to discover what turns on ALX3 to pinpoint the exact evolutionary change responsible for the striped pattern, Patel says.

Alpine marmot couple wait for their turn, video


This 2016 video shows an Alpine marmot couple waiting for their turn, in the Karwendel mountains in Austria.

Thim Kooijman made this video.

Naked mole-rats and pain, new research


This video says about itself:

18 June 2015

Naked mole-rats are some of the most fascinating members of the animal kingdom – but just how unique are they? Turns out, they diverged from their nearest relative more than 31 MILLION years ago! Field Museum curator Dr. Bruce Patterson, and Yale postdoctoral researcher Nate Upham have determined they ought to be in their own scientific family. Now, can someone please update their Wikipedia page?

Read more about this discovery on The Field Museum’s website.

Here‘s the abstract for the paper:

Patterson, B. and Upham, N. “A newly recognized family from the Horn of Africa, the Heterocephalidae (Rodentia: Ctenohystrica).” (abstract)

Shout-out to Jillian at Chicago’s Lincoln Park Zoo for allowing us to get footage of their colony!

HUGE thank-you to Bruce and Nate for their help with this episode! And, congratulations to Bruce for being the 2015 recipient of the prestigious C. Hart Merriam Award from the American Society of Mammalogists!

From Science News:

Hot and spicy pain signals get blocked in naked mole-rats

by Laura Sanders

5:23pm, October 12, 2016

Like Marvel’s surly superhero Luke Cage, naked mole-rats are seemingly indestructible, hairless creatures that are impervious to certain kinds of pain. This last power has puzzled researchers, because like other mammals, mole-rats have functional versions of a protein called TRPV1, which responds to painfully hot stimuli.

It turns out that a different protein, TrkA, is the key to the missing pain signals, Gary Lewin of the Max Delbrück Center for Molecular Medicine in Berlin and colleagues report in the Oct. 11 Cell Reports. Usually, TrkA detects inflammation and kicks off a molecular reaction that produces pain sensation by activating TRPV1. But naked mole-rats produce a version of TrkA that doesn’t trigger this pain cascade.

That means that certain nerve cells don’t become more sensitive after encountering something hot, such as capsaicin, a molecule that puts the burn in spicy peppers. Because naked mole-rats spend their time in hot African climates, the rodents might have evolved to not need the pain signals that come from heat, the authors speculate.

Birds and squirrels in Cornwall


This video from Britain says about itself:

Videos & Sounds for Cats to Watch and Listen To – Birds and [Grey] Squirrels Being Awesome NEW

Filmed in October 2016

Video Produced by Paul Dinning – Wildlife in Cornwall

The birds include great tit, coal tit and nuthatch.

American chipmunk’s corn cob food, video


This video from the USA says about itself:

29 September 2016

Chipmunk shucks an entire ear of dried corn in record time and stores it away for cold winter days. That is not an easy task when the corn cob is bigger than you are! Admirable little rodents with an impressive work ethic and survival skills.