It's answer time! I love this question, because there's so much that we can learn about behavior from traces in the fossil record. For a lot of these, you might at first think "there's no way we could know this -- we weren't there!"
And yet...
Let's start with Anchiornis. "What colors were dinosaurs?" is a great example of things we once said we could never know, but now often can. Thanks to microscopic structures in feathers called melanosomes, (which fossilize!) we can tell what colors many dinosaurs were!
From shiny blue-black feathers like corvids, to bright colors like hummingbirds, we can now fill in the palettes of the Cretaceous with more than our imaginations. smithsonianmag.com/science-nature…
What about matriarchal mammoths? How could we possibly know that? There are a few lines of evidence: 1) in "death traps" like the Mammoth Site or La Brea, remains are disproportionately juvenile males, which is consistent with them losing the herd's wisdom when they go solo.
2) We can tell the sex of animals from their fossilized trackways (size, gait), and in cases where groups of tracks are found together, we can recreate family structures. smithsonianmag.com/science-nature…
3) Mammoth tusks have growth rings, like trees! Female tusks tend to have evenly spaced rings on average, except when they have babies (which uses resources). Males have even rings until puberty, when they become much closer, signaling a period of poor diets as "teenagers."
Taken together, and compared with modern elephants (which mammoths and mastodons were close cousins of), the evidence points to mammoths having matriarchs-- including cultural knowledge about landscapes and resources that was passed down through generations.
Tyrannosaurus rex's speed has been debated, with some estimates as high as 20 m/s. These are based on trackways (imprint depth, distance between footprints), and biomechanical models. A 2002 study found that to run that fast, 86% of T. rex's body mass would have been in its legs!
Some of the more recent studies suggest a slower running speed closer to 5 m/s, at least for adults. And a study last year that focused on T. rex's tail found an average walking speed of ~3 mph. smithsonianmag.com/smart-news/new…
But if the slower running speeds are accurate, does that mean T. rex was a scavenger, not a ferocious predator? It was probably both, based on extensive research, as @Laelaps has written...and that's been widely accepted for a couple of decades now. nationalgeographic.com/science/articl…
So if A, B, and C are correct, that means D is the lie. As much as I want these big, black-bear-sized giant beavers to have been ice age dam-builders, there's no evidence that they did. And their teeth appear to be poorly suited to chewing on wood (though they were rodents!).
There have been giant ice age dams, but these were caused by ice sheets damming meltwater, which would burst in massive, catastrophic floods! pbs.org/wgbh/nova/arti…
If you'd like to learn more about function and behavior in the fossil record, this is a pretty accessible review article that has some fun and lovely examples. journals.plos.org/plosbiology/ar…
Do you get a thrill thinking about ancient beasts and their fascinating lives? Wishing I would just stop posting these silly quizzes already? Back @MakeAPlanetPod, so we can bring the past to you, instead of testing you on it every day! kickstarter.com/projects/makea…
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A lot of the debates about whether to bring politics into science, teaching, or other spheres of public life would be easily avoided if people remembered that being political is not the same as being partisan.
Politics involves how decisions are made, how power is structured, and how resources are allocated within and among groups.
Partisanship is an allegiance to a specific faction, party, or politician.
The two concepts are related, but they are not the same.
My research has policy implications. My ability to do my job is influenced by state and federal funding for research and education. We teach students to be well-rounded, informed members of society. We exist within systems that affect who gets to do science, or get an education.
Over a month after the vote, the think pieces on the "rejected" Anthropocene are still coming strong, so I wanted to take a moment to (finally!) offer some background and thoughts about the vote, the process, and what it all means.
Geologists define different intervals in Earth's past so we can share a common language. Earth's 4.5 billion year history is divided into a series of eons (longest), eras, periods, epochs, and ages (shortest), based on visible changes in rock layers and fossil ecosystems.
For example, the Cenozoic Era began 66 million years ago with the impact that killed the dinosaurs. Within that, the Paleocene (66 to 56 mya) was the first epoch within the Paleogene Period (66 to 23 mya). Each is defined by rock layers that record extinctions and climate events.
Last December, a @DukeU Magazine article explored the "uncertain future" of the Duke Herbarium.
The scientific community is now learning that Duke has decided that this facility will be closed. This is bad, and here's why.dukemag.duke.edu/stories/nowher…
A herbarium is basically a collection of plant specimens that are preserved for research and teaching. They're a vital resource to help scientists identify species, understand changes in biodiversity patterns, or even changes in flowering time or other climate change impacts.
Herbaria require resources and space, as well as staff, who use the collections for research and outreach, and who assist visiting scientists to conduct research. Many collections are digitized, but the actual specimens have tons of value. Internet photos aren't enough.
If you say humanity is doomed to extinction and that nothing we can do can prevent total climate breakdown and ecosystem collapse, I need you to know's just as unscientific as saying there's no climate crisis.
I don't platform disinformation. I don't care what kind it is.
Sadly, I've learned that just as there's no convincing the dismissives the climate crisis is real, there's no convicing defeatists that this isn't pass-fail, and that our work will always matter. I only have so much time and energy. It needs to go where it can be of the most use.
Most defeatists seem to come from demographics that haven't historically faced the loss of their bodily autonomy, rights, homelands, or cultures. I empathize with those experiencing their first-ever existential threats, but I really wish their first instinct wasn't to give up.
I woke up this morning full of pain at so much violence, to each other and to the planet. I wrote a short message to my lab, and it helped me see a clearer path. I'm sharing it here in case it helps you, too.
Witnessing trauma is its own kind of trauma, especially in a society that wants us to suppress that trauma so we can continue to function as well-oiled cogs. We don't have a lot of good tools for how to bear witness without becoming numb. And we cannot become numb.
I wish I had the answers, but I'm fumbling through this, myself. What I can say is that when things are difficult, anything we can do to show up for each other and our communities makes a difference. The fabric of society is threadbare and torn; we must patch and weave.
Since 2009, the Anthropocene Working Group has been trying to decide whether geologists should revise the geologic timeline to include a new epoch defined by human impacts, and if so, when. 🧵
If you're not familiar with this project or the debates about when the Anthropocene would start, here's a thread I did on exactly that:
Now that you're all caught up on golden spikes, here's an update:
Today, the Anthropocene Working Group (AWG) announced their recommendation, which is that we should have a new geologic epoch, and it started in 1950, as recorded in lake sediments from Crawford Lake, Ontario.