Monday, November 30, 2015

This Animal Looks Like a Penis With Teeth... But It's Even Stranger Than That

This is a naked mole rat.

Yes, this is arguably the freakiest-looking animal on Earth.
Photo by Roman Klementschitz at Wikimedia Commons.

Naked mole rats are rodents that live in underground tunnels under East African savannas and grasslands. There's nothing all that strange about that... but how they have adapted to this lifestyle is unique... and, quite frankly, amazing.

For one thing, to cope with the low oxygen levels of the subterranean environment, naked mole rats have very low metabolisms and breathing rates. One of the biggest uses of metabolic engines in mammals is to produce our own body heat. These little guys have cut this big expenditure by being what may be the only ectothermic mammals on the planet. Ectotherms are animals like most fish, amphibians and reptiles that get most of their body heat from their environment, rather than making it themselves. Because naked mole rats want to exchange heat with their environment, they want to eliminate insulation... giving them their hairless and fatless bodies. Now when they bask in the sun at their tunnel entrances or huddle with their family they can take in all that warmth without anything getting in the way.

There are some benefits to having low metabolisms and not using much oxygen: Naked mole rats live for nearly 30 years (compared to 1-3 years in regular rats). Oxygen creates free radicals, highly reactive chemicals that cause damage to DNA, leading to a wide range of diseases. Naked mole rats don't just use less oxygen, but they have special proteins that are resistant to these damaging chemicals. They also produce a specialized super-sugar that has essentially eliminated cancer in this long-living species. What's more, these elderly rodents have managed to avoid dementia and osteoporosis, traits we hope to learn more about through ongoing research.

Naked mole rats have also developed some unique sensory traits. Living with your entire extended family in underground burrows means that you live in high levels of carbon dioxide and walls saturated in pee. These little guys don't even have any body hair to protect their pink skin from all that burning ammonia. Their solution: get rid of pain. These guys have no pain receptors for noxious chemicals like acids or capsaicin (the stuff that makes hot peppers hot). Furthermore, they are lacking a specific neurotransmitter, called substance P, that other mammals use to send many pain signals. Since naked mole rats have less need for sensation in their skin, they have developed brains that have repurposed about 30% of the sematosensory cortex (the part of the brain that interprets touch sensations) to their digging teeth!

Perhaps the strangest quality of all for these animals is their behavior. Naked mole rats are one of only two known mammals that are eusocial (the other being the Damaraland mole rat). Eusociality is a social organization common among bees, wasps, ants and termites, in which the colony has castes that include queens, workers and soldiers. Among naked mole rats, there is a single queen in the colony that mates with a few dominant males; workers that dig the tunnels, gather food, and care for the young; and soldiers that protect the colony from predators. Workers and soldiers are all reproductively sterile with undeveloped gonads and low hormone levels. However, if the queen dies, one of the non-reproducing females will go through puberty and take on her role as the new queen.

Now that you know that naked mole rats are so much more than just a "freaky thing", enjoy this naked mole rat rap (or maybe even a whole episode of Disney's Kim Possible, which features Rufus, the naked mole rat):

Monday, November 23, 2015

The Science Life 2

The life of a scientist is increasingly stressful. Sometimes it helps to relieve stress in song:

“Bad Habits” by Nathaniel Krefman (Parody of “Magic” by B.o.B. featuring Rivers Cuomo):

“Eight Days a Week” by the UC-Berkeley Molecular and Cell Biology Department (Parody of “Eight Days a Week” by The Beatles):

“The Tale of a Post Doc” by James Clark at Aerospace Medicine at King’s College London (Parody of "Bohemian Rhapsody" by Queen):

Vote for your favorite in the comments section below. If you would like to see more music videos on the life of a scientist, check out The Science Life. And if you feel so inspired, make a video of your own, upload it on YouTube and send me a link to include in a future post!

Monday, November 16, 2015

Animal Mass Suicide and the Lemming Conspiracy

Ticked off Norway lemming doesn't like gossip!
Photo from Wikimedia Commons by Frode Inge Helland
We all know the story: Every few years, millions of lemmings, driven by a deep-seated urge, run and leap off a cliff only to be dashed on the rocks below and eventually drowned in the raging sea. Stupid lemmings. It’s a story with staying power: short, not-so-sweet, and to the rocky point.

But it is a LIE.

And who, you may ask, would tell us such a horrendous fabrication? Walt Disney! Well, technically not Walt Disney himself…

Today I am revisiting an article I wrote in the early days of The Scorpion and the Frog, explaining animal mass suicide and the role of Disney in creating one of the greatest animal behavior hoaxes of all time. You can read the article in it's entirety here.

Monday, November 9, 2015

Caught in My Web: The Intelligence and Creativity of Crows, Octopuses, Monkeys, Fish and Dogs

Image by Luc Viatour at Wikimedia.
For this edition of Caught in My Web, we marvel at animal intelligence.

1. Joshua Klein talks about crow intelligence and their potential for training in this fun TED talk.

2. Jason Goldman at io9 explains an amazing discovery that Atlantic cod can also innovate to solve problems.

3. Sarah Williams at Science explains research out of Harvard that shows that untrained rhesus monkeys can do math and we can use this to learn about how we think.

4. A veined octopus shows off his imagination as he creates a “hiding” place:

5. And last, but not least, three shelter dogs were taught to drive! Here are the results:

Monday, November 2, 2015

Body Armor is Not Always for Protection

When we see an animal covered in scales and plates, we assume that it has this armor to protect itself from predators. It seems obvious, which is probably why scientists had not really tested it… until now. And they found that it is not necessarily true.

An armadillo girdled lizard has some impressive body armor, but does it do what we think it does?
Image by Handre Basson at Wikimedia Commons.
Today at Accumulating Glitches, I talk about new research on the functions of plates and scales in cordylid lizards. Check it out here.

And to learn more, check this out:

Broeckhoven, C., Diedericks, G. and le Fras Mouton, P. What doesn’t kill you might make you stronger: functional basis for variation in body armour, Journal of Animal Ecology, 84, 1213–1221 (2015). DOI: 10.1111/1365-2656.12414.