Happy Christmas! Here’s why giraffes have short necks!
December 24, 2020
On 22nd December 2020, I gave this talk (via Zoom) to Martin Sander’s palaeontology research group at the University of Bonn, Germany. And now I am giving it to you, dear reader, the greatest Christmas present anyone could ever wish for:
It’s based on a 2013 paper written with Matt Wedel, which itself goes back through many years slow gestation, originating in a discussion on a car journey in 2008. I must tell the full story some time; but not this time.
In this talk, I start by showing in a hopefully vivid way how very much longer sauropods’ necks were than those of any other animal. Then I explain six of the features that made those very long necks possible: no constraint on vertebral count; small, light heads that did not process food; absolutely large bodies with a quadrepedal bauplan; an avian-style respiratory system; air-filled cervical vertebrae; and elongated neck ribs.
If you want to know more, see that Wedel and Taylor (2013) paper!
Finally, my thanks to René Dederichs, a Student of Paleontology in Martin Sander’s work group at the University of Bonn. He organized this event, and recorded the talk for me.
References
December 25, 2020 at 5:25 pm
Beautiful to finally hear/see the presentation itself! Also didn’t know that tendons had more tensile strength… but then why do they ever ossify? Does this mean that these ribs are really destined genetically to be bone, like the rest of the vertebra (or the main skeleton in general), and not juvenile tendons that get replaced by bone over time? [I say “destined” because I was wondering recently why I didn’t break so many bones when I had major rollerblade wipeouts in my 20s, and I realized – duh, if there was any cartilage still there then, it’s gooooone now, lol]
Also, i have to assume Mike is pronouncing Matt’s last name correctly, and altho I don’t think it came up in conversation in person, I wasn’t. Apologies!
And merry Christmas to all, not just to Mike and Matt – I love learning from all of the commenters, I apologize that as an aficionado, I take more knowledge than I can possibly give with my questions and speculative stabs in the dark.
December 25, 2020 at 5:34 pm
Sorry, “why did they ossify”, meaning, is there any reason besides that a bony structure can be made hollow like the bird wings – but I had been under the impressions these ribs were more narrow and solid? And I can attest that even mammalian bone is (maybe “was” for me) at least somewhat flexible, I clearly remember an incident where I was sure in the moment my tibia was about to break – I could for sure tell it bent. Luckily for me, it only left what is now (almost 30 years later) a dark mark on my shin at the contact point. Not even a real bruise where it hurt, pretty much just skin there.
Also, I don’t mean to brag about injuries, I find many of them to be amusing after the fact (and I try to adopt that line of thought ASAP because I can’t undo them), and hopefully can offer some insight beyond what I personally experience.
December 26, 2020 at 11:06 pm
Tendons stretch under tension. Bone stretches much less. If you don’t want a tendon to stretch, ossify it.
Bone is stronger under compression than under tension, but under tension it’s still stronger than a tendon or a ligament, IIRC.