Tag Archive: birds

This is a 2008 Nova (PBS) program on a dinosaur (Microraptor) that is still the subject of breaking news, so in some ways it is pretty dated. But it also gives a good view of how scientific controversies are resolved (or not) and some of the tools of paleontology.

Most people, thinking of dinosaurs, think big. Tyrannosaurus. Stegosaurus. Triceratops. Even the raptors of Jurassic Park were large, though not overwhelmingly so.

But how much of that is due to a combination of publicity (the biggest of anything is news) and preservation bias? How many of today’s birds ever fossilize?

Luckily there are formations in which fossils are preserved with extraordinary fidelity. One such formation, in China, has yielded numerous specimens which retain vestiges of fur or feathers, leading to the recognition that feathers were widespread on dinosaurs. Most of the feathers seem to have been more for warmth or display than for flying, as they lack the aerodynamic asymmetry seen in the flight feathers of today’s birds.

This is not the case for Microraptor, which had asymmetric flight feathers on all four limbs.

But how were those limbs used in flight? Could the animal actually have spread its rear limbs horizontally, as first suggested by Xu Xing when he initially described it?

The controversies explored in this DVD are twofold: how did Microraptor use its extraordinary feathered hind limbs, and are birds in fact dinosaurs?

Birds have all of the skeletal features used to state that a fossil is a dinosaur. Given the evidence of many other feathered dinosaurs from the same Chinese formation, I have problems seeing birds as anything other than flying dinosaurs. The origin of flight — from gliding out of trees or scrambling up from the ground — is a completely separate question, and should have been separated in this way by the scientists involved.

One argument repeatedly made by one of the scientists strikes me as as based on a rather poor assumption. This is that “dinosaurs didn’t climb trees, so flight could not have originated by dinosaurs gliding down from trees.” Who says dinosaurs couldn’t have climbed trees? Certainly the big ones couldn’t have, but there is increasing evidence that some dinosaurs were considerably smaller than a turkey, and turkeys (the original wild ones, not their domesticated descendants) certainly roost in trees. Lack of evidence the dinosaurs climbed trees is not the same as evidence that they did not climb trees.

Leaving that aside, the bulk of the DVD follows experimental work trying to reconstruct the 3-dimensional skeleton of Microraptor from the fossils (often flattened in the fossilization process) followed by wind tunnel work to asses the probable way in which it used its limbs to fly or glide.

The DVD is worth watching for this experimental work, though none of the work shown should be considered conclusive. It is worth pointing out the actual fossils are still giving up more information, the latest being evidence that this animal probably had iridescent blue-black feathers. Neither this DVD nor the microraptors shown in Prehistoric Park show this color.

Ice bird carving in front of the hospital lab.

The sun rose at 7:43 this morning and will set at 6:22 for 10 hours 39 minutes of daylight. Spring may not be here officially, but sun on snow was almost too bright to look at Sunday. My snow stake agrees with the official snow depth: 20”. That’s actually not too bad for this time of year; not so much that it will take forever to melt, but enough to insulate the ground from getting any colder. Regretfully, I’ll be back to “sun will rise” next week—this post goes live at 8 am my time, and daylight savings will once again put sunrise before I get up. Only for the one week, though. We’re gaining 6 min 45 sec a day, and by March 19 I’ll again be getting up after sunrise.

It’s been on the cold side—temperatures above zero in the middle of the day but well below zero at night. No sign of melting yet, and I’m going to try to photograph the ice sculptures before they start thawing this year. (Watch for tomorrow’s post.) They are, however, beginning to accumulate snow. Never very much at a time, but we seem to get a fraction of an inch a day rather often this year.

The commonest real birds this time of year.

I ordered my bean and squash seeds yesterday. Rocdor (yellow) and Gina (Italian type), both of which I know do well up here, and are actually earlier than the regular green beans, are my bean varieties of choice; Gold Rush and Contender for zucchini. I enjoy visiting the local greenhouses too much to order seeds for herbs and flowers I know will be available as starts locally. Besides, I try to avoid pesticides indoors, and my seedlings almost always get bugs if I try to grow too many.


My goals for March were:

1. Learn to use at least one legal method of getting images other than photos I’ve taken on my blog. (I’d love to have some shots of Africa on Jarn’s Journal, for instance.) Progress? Mostly looking up creative commons on Google, and finding a few pictures I’d like to use. I’ve also talked to a friend about using some of his African photos.

2. Continue to blog at least 5 days a week. (I’m doing 7 now, but I’ve signed up for a number of adult classes in March.) Progress? So far I’ve blogged every day and have posts lined up for 10 of the remaining 26 days.

3. Edit Chs 2 and 9 of my WIP to give more showing, less telling. Progress? I think I have Ch 2 done.

4. Participate in at least one Platform-building challenge–hesitate to commit for more without knowing what they are. Progress? I accepted the first Campaign Challenge and posted the result. Not sure if achieving this goal in February counts, though.

And I received notice that my second novel, Tourist Trap, is a finalist in the Reader Views Literary Awards contest! So I’m on track, at least.