Penguin brains not changed by loss of flight

March 1, 2016
This is an ancient penguin skull and endocast. Scale bar is 2.5 cm and letters indicate parts of the brain: ce, cerebellum; el, endosseus labyrinth; fl, floccular lobe; ol, optic lobe; os, occipital sinus impression; pb, pituitary bulb; t, telencephalon; w, wulst. Credit: James Proffitt

Losing the ability to fly gave ancient penguins their unique locomotion style. But leaving the sky behind didn't cause major changes in their brain structure, researchers from The University of Texas at Austin suggest after examining the skull of the oldest known penguin fossil.

The findings were published in the Journal of Anatomy in February.

"What this seems to indicate is that becoming larger, losing flight and becoming a wing-propelled diver does not necessarily change the [brain] anatomy quickly," said James Proffitt, a graduate student at the university's Jackson School of Geosciences who led the research. "The way the modern penguin brain looks doesn't show up until millions and millions of years later."

Proffitt conducted the research with Julia Clarke, a professor in the Jackson School's Department of Geological Sciences, and Paul Scofield, the senior curator of Natural History at the Canterbury Museum in Christchurch, New Zealand, where the skull fossil is from.

The skull is from a penguin that lived in New Zealand over 60 million years ago during the Paleocene epoch. According to Proffitt, it likely lived much like today. But while today's penguins have been diving instead of flying for tens of millions of years, the change was relatively new for the ancient penguin.

This is a comparative representation of waterbird endocasts (as viewed from the top of the brain) mapped onto a supertree of waterbirds. The supertree shows evolutionary relationships between different bird species. The endocast of the penguin the researchers studied is Waimanu sp. Credit: James Proffitt

"It's the oldest [penguin] following pretty closely after the loss of flight and the evolution of flightless wing-propelled diving that we know of," Proffitt said.

The shape of bird skulls is influenced by the structure of the brain. To learn about early penguin brain anatomy, Proffitt used X-ray CT-scanning to digitally capture fine features of the skull's anatomy, and then used computer modeling software to create a digital mold of the brain, called an endocast.

The researchers thought that loss of flight would impact brain structure—making the brains of ancient penguins and modern penguins similar in certain regions. However, after analyzing the endocast and comparing it to modern penguin brain anatomy, no such similarity was found, Proffitt said. The had more in common with skulls of modern relatives that both fly and dive such as petrels and loons, than modern penguins.

It's difficult to know why modern penguins' brains look different than their ancestors' brains, Proffitt said. It's possible that millions of years of flightless living created gradual changes in the brain structure. But the analysis shows that these changes are not directly related to initial loss of flight because they are not shared by the ancient penguin brain.

However, similarities in the brain shape between the ancient species and diving birds living today suggest that diving behavior may be associated with certain anatomical structures in the .

"The question now is do the old fossil penguins' brains look that way because that's the way their ancestors looked, or does it have something maybe to do with diving?" Proffitt said. "I think that's an open question right now."

Explore further: New fossil skulls reveal insights about penguin brain evolution

More information: J. V. Proffitt et al. Novel insights into early neuroanatomical evolution in penguins from the oldest described penguin brain endocast, Journal of Anatomy (2016). DOI: 10.1111/joa.12447

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9 comments

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betterexists
1 / 5 (3) Mar 01, 2016
JUST MAKE THEM FLY!
What is Gene Editing for?
So Many Birds are there to donate their Genes to it.
It ALREADY HAS Wings.
viko_mx
2 / 5 (8) Mar 01, 2016
I do not know why the author of this article is left with the impression that penguins have ever flown. They have fins which are used for swimming. Penguins have an affinity for swimming rather than flying. So they are constructed.
Vietvet
3 / 5 (6) Mar 01, 2016
I do not know why the author of this article is left with the impression that penguins have ever flown. They have fins which are used for swimming. Penguins have an affinity for swimming rather than flying. So they are constructed.


LMFAO!

Penguins don't have fins, they have modified wings. Damn, Viko, you're an idiot.
Captain Stumpy
3.4 / 5 (5) Mar 01, 2016
LMFAO!

Penguins don't have fins, they have modified wings. Damn, Viko, you're an idiot.
they also FLY... just not through the air

LOL
antigoracle
2.3 / 5 (3) Mar 01, 2016
Penguins don't have fins, they have modified wings

Hmm... since whales evolved from a land animal, do they have fins or a modified leg?
BartV
1.7 / 5 (6) Mar 01, 2016
Science: Penguins dive instead of fly.

Fantasy and not scientific facts:
* Penguins have lost the ability to fly.
* Penguins have left the sky behind.
* Penguins have had gradual changes in the brain structure.

Judging from just a logical point of view, this article is most fantasy and little science.

Captain Stumpy
3.7 / 5 (3) Mar 01, 2016
Hmm... since whales evolved from a land animal, do they have fins or a modified leg?
@AntiG
Like in our own bodies (Coccyx), you can see evidence of a past in whale bones too...some bones are modified, some missing ... a few of the links are for a junior audience, but still good links that answer your question
you can see some info on it here: http://evolution....grams_03

http://seymourcen..._Key.pdf

http://www.ftexpl...os3.html

bschott
1 / 5 (3) Mar 02, 2016
@AntiG
Like in our own bodies (Coccyx), you can see evidence of a past in whale bones too


None of your links address either comment.

Penguins don't have fins, they have modified wings

Hmm... since whales evolved from a land animal, do they have fins or a modified leg?


All limbs on all animals used to be something else according to evolution. Wales use limbs that WERE legs (if you believe the theory) but we now call fins, to help their motion in their environment, Penguins use limbs that were wings at one time to do the same. They are now used as fins or flippers, somebody is just being touchy about terminology out of atheistic spite...and somebodies friend, as usual missed the mark completely.

Judging from just a logical point of view, this article is most fantasy and little science.


You can cut and paste that at will here.
viko_mx
1 / 5 (3) Mar 02, 2016
If we assume that the penguins perform underwater flying, we can accept that they really have wings with which maneuvering during underwater flight. From th eather hand if the penguins have modified wings with which can make maneuvers underwater, so the whales have modified fins with which can fly.

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