Jaws on legs and feathered dinosaurs

So not only did Tyrannosaurs have feathers, they had a Mini Me as well. Or rather they had midget ancestors.

I lost a bet to a workmate the other week. Well, only half lost a bet. The workplace banter had turned to the Tyrannosaurus rex for some reason, and my colleague made the assertion that Tyrannosaurs had feathers. I rejected that assertion wholeheartedly as I had always thought that T. rexes had some kind of leathery-scaly reptilian skin. After all, Steven Spielberg could not have gotten it wrong, could he?

So for the price of me making her a cup of tea without any comments about the two to three sugars she takes in her cups of black tea (if she was right), I set her the challenge of finding scientific evidence that the T. rex had feathers. Were she wrong, or couldn't find the evidence, I'd be able to occasionally, gently hassle her about the sugar content in her tea (you see, I care about friends facing risks of developing Type 2 diabetes, but I don't think I'm mean or too onerous about it).

The result was half-and-half. My workmate had very quickly dug up the National Geographic's pictures of the Chinese finding a new dinosaur some years ago – a tyrannosauroid that had feathers or some kind of early or hairlike primitive feathers. Or proto-feathers. As so:

I counted with the argument that this tyrannosauroid, Dilong paradoxus, was actually a different species from the Tyrannosaurus rex – in fact an early relative of T. rex, and it was the T. rex that we'd had the bet about.* Either way, the feathered tyrannasouroid created a fair bit of interest in the office.

To top this was the recent news of the Mini T. rex – a relatively tiny ancestor of the T. rex that was only approximately three meters long. The ABC reports that the Raptorex, also found in China, 'weighed only about 60 kilograms and was nearly 100 times smaller than T. rex'.

It may have been as small as an adult human, but it was still letha. As Dr Paul Sereno, paleontologist with the University of Chicago, put it, “It was jaws on legs.”

That ABC piece has some really interesting ideas about why the Raptorex poses some intriguing rethinking about the evolution of the T. rex. For one, the fossil find suggests that 'the skinny arms evolved not in order to help it offset a heavier overall bodyweight, but instead as a trade off for agility and speed.' But there was no suggestion of whether the 'Mini Me' T. rex had feathers too.

I reckon the might of the T. rex, for all its agility and speed, is overated. Those small, skinny arms make me doubt it.

*PS. The bet: while I insisted that my workmate's feathered tyrannosauroid was a seperate, earlier species, I made her a cup of tea with two sugars anyway.