A bowhead whale’s highly (but not entirely) reduced pelvis. Image via Wikimedia Commons.
Thanks to a remarkably good fossil record, it’s now well established whales and dolphins evolved from land mammals, their forelimbs adapting into flippers, and their hind-limbs almost entirely disappearing. If you’d asked me yesterday what’s going on with that almost—the last vestiges of the hip bones that whales retain, which have no legs to support or direct contact with the rest of their skeletons—I’d have told you they were evolutionary leftovers, and probably going to disappear in another million years or so. I think a lot of other evolutionary biologists (those who aren’t whale specialists, anyway) would’ve agreed with me. But it turns out we’d have been wrong.
As Carl Zimmer describes, a paper recently published in the journal Evolution points out that whales’ hips do have one remaining function, an important one—they anchor muscles that control the penis. And that function is under ongoing sexual selection.
The more promiscuous a [whale] species was, the bigger its pelvis bones tended to be. The scientists also found that as whales evolved to become more promiscuous, their pelvic bones changed shape. These changes weren’t part of some general change to their skeleton, however. The ribs near the hips didn’t show the same patterns of size and shape change.
I strongly recommend Zimmer’s whole article, and you can also read the original research article in Evolution.
Did you know that the journal BMC Ecology has an annual photo competition? Harold et al. has recently announced the 2014 winners and the images are incredible! Check out the full, open-access article here (or you can “cheat” and view some of the images as a slideshow here). Lookin’ good, Ecology!
Fig. 3 from Harold et al. Their caption is: “Winner:behavioural and physiological ecology. “Camponotus morosus ant being attacked by a parasitoid phorid fly (Diptera: Phoridae). At the moment of the attack the ants were involved in a intra specific fight between two different ant nest and presumably the fly detected the ants because of the alarm pheromones released during the fight.” Attribution: Bernardo Segura.”
A fungus called Cryptococcus gattii, has long known to be infective to humans… even though it’s found on trees.
This has particularly been a problem in Southern California, where people have been getting sick from C. gattii for yeas, and no one knew which tree was harboring the fungus. Find out who the culprit is and how they figured it out!
Developing successful student – professor interactions can be a very challenging aspect of teaching at the university level. Getting students to ask questions and engage in a class is very hard, especially in large introductory courses. One professor tried to combat this problem using a radical strategy, banning students from emailing her unless they were setting up a time to meet in person. The crazy part is that the strategy seems to have worked. She reports developing better interactions with her students, who actually evaluated her as being more accessible than in previous semesters without such email bans.
Check out the full article here.
What do you think? Would you ban students from emailing you questions about the course? Do you think students would accept and support such as strategy? Would you prefer students to phone you with questions, rather than email?
As a follow-up to CJ’s post about hummingbird moths—more generally known as hawk moths—let me recommend this episode of Plants are Cool, Too, which features the work of Chicago Botanic Garden conservation scientist Krissa Skogen. At White Sands National Monument, Skogen tracks the nectar rewards that attract hawk moths, and how far the moths carry pollen.
Looks like this guy:
Is the cartoon version of this guy:
It walks. It breathes air. And apparently it can adapt to terrestrial life relatively “easily”.
The scientists raised groups of bichir on land for eight months to find out how they would differ from bichir raised in the water. They found that the land-raised fish lifted their heads higher, held their fins closer to their bodies, took faster steps, undulated their tails less frequently and had fins that slipped less often than bichir raised in water. The land-raised fish also underwent changes in their skeletons and musculature that probably paved the way for their changes in behavior. All in all, these alterations helped bichir move more effectively on land.
There’s a video too!
Last week NPR posted an excellent article about what can only be the coolest pollinator. Ever.
“like a flip-flop that doubles as a beer bottle opener; an optical illusion; a labradoodle; a frenemy, the hummingbird moth falls into that cryptic category of transformers in life that are more than one thing” – Linton Weeks ” What Exactly is that Birdlike Thing?”