strange behaviors

Cool doings from the natural and human worlds

  • Richard Conniff

  • Reviews for Richard Conniff’s Books

    Every Creeping Thing: True Tales of Faintly Repulsive Wildlife: “Conniff is a splendid writer–fresh, clear, uncondescending, and with never a false step; one can’t resist quoting him.” (NY Times Book Review)

    The Species Seekers:  Heroes, Fools, and the Mad Pursuit of Life on Earth by Richard Conniff is “a swashbuckling romp” that “brilliantly evokes that just-before Darwin era” (BBC Focus) and “an enduring story bursting at the seams with intriguing, fantastical and disturbing anecdotes” (New Scientist). “This beautifully written book has the verve of an adventure story” (Wall St. Journal)

    Swimming with Piranhas at Feeding Time by Richard Conniff  is “Hilariously informative…This book will remind you why you always wanted to be a naturalist.” (Outside magazine) “Field naturalist Conniff’s animal adventures … are so amusing and full color that they burst right off the page …  a quick and intensely pleasurable read.” (Seed magazine) “Conniff’s poetic accounts of giraffes drifting past like sail boats, and his feeble attempts to educate Vervet monkeys on the wonders of tissue paper will leave your heart and sides aching.  An excellent read.” (BBC Focus magazine)

  • Wall of the Dead

  • Categories

  • Advertisements

Gigunda Rodent. Yes, Definitely Bigger Than a Housecat

Posted by Richard Conniff on February 6, 2015

O.k, New Yorkers, better stop your whining. Check out this report from the BBC:

Biggest rodent ‘fought with teeth’ like tusks

Josephoartigasia monesi (artist's impression)

The Big Fella

Scientists say the largest ever rodent probably used its huge front teeth like tusks, defending itself and digging with them instead of just biting food.

The bull-sized cousin to the guinea pig died out around two million years ago.

Based on a CT scan of its skull and subsequent computer simulations, its bite was as strong as a tiger – but its front teeth were built to withstand forces nearly three times larger.

This suggests that its 30cm incisors were much more than eating implements.

Researchers from York in the UK and Montevideo in Uruguay published the work in the Journal of Anatomy.

Only a single fossilised skull has been found belonging to this 1,000kg South American rodent, known as Josephoartigasia monesi. Unearthed in Uruguay in 2007, the animal lived in the Pliocene period – a warm era when large mammals were relatively abundant, including the first mammoths.

It remains the largest rodent ever discovered.

To study the mechanics of the skull,

the team performed a CT scan of the skull and used it to reconstruct a computer model – including its missing lower jaw, which they copied from a related species.

They then tested this model using “finite element analysis”, a technique from engineering which calculates stresses and strains in complex objects.

skull reconstructionThe animal’s incisors (green) were found to be much stronger than necessary for biting

The forces predicted during biting were large, and similar to a tiger’s jaw. But the rodent’s big incisors appear “overengineered” even for that sort of strain – and would probably stand up to much stronger forces.

So the researchers believe the front teeth must have been used for tasks that required extra muscles, like the neck, as well as the biting action of the jaw muscles themselves.

“We concluded that Josephoartigasia must have used its incisors for activities other than biting, such as digging in the ground for food, or defending itself from predators,” said the study’s first author Dr Philip Cox, an anatomist at Hull York Medical School and the University of York.

“This is very similar to how a modern-day elephant uses its tusks.”

size comparison of Josephoartigasia monesi The extinct rodent (right) pictured in comparison with a human and a pacarana, its closest living relative



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s