Silhouetting Terror

(C) Tuomas Koivurinne

Throughout the course of this blog we have never been disappointed by the art of Tuomas Koivurinne. A bird like Titanis could be illustrated in either very magnificent poses or in some fairly stereotypically mundane poses. Combining the two (awesome bird and awesome artist) we get to see a view that is as magnificent as the skeletal remains indicate the bird to be. More often than not with birds the best illustrations draw on numerous versions of pigmentation hypotheses; featuring parrot-like terror birds that are almost more colorful than they are deadly. This illustration takes the worry of correct coloration and pigmentation away, for the most part, leaving us with a Titanis that could be anywhere between a crow-like jet black and perhaps a slightly lighter brown. Either way, of course, the sunset has hushed the tones of the feathers and the bird itself is silhouetted perfectly against the sky. It is not silhouetted so much that the important aspects of the terror inspiring of the bird have been subdued. The angry looking eyes, under their broad superorbital shelf of bone are plainly seen and they are looking angrily over the foreground and up at the sky. The broad bill and large feet are also clearly evident, though the feet are not particularly highlighted. The feet, mostly used for running, would have been used to crush and hold prey items under the weight of the bird as well as the power of the legs. The feet would have been quite a dual threat. The bill was most likely used as a hatchet (special thanks to Federico "Dino" Degrange for describing the Phorusrhacid bill at our meeting last week) to stun and kill prey. The wings of this bird were, as they are with many Phorusrhacids, atrophied and weak. Unlike those of ostriches, this running bird did not use its wings, it would appear, to balance as significantly while running at high speeds. A viable alternative hypothesis to this idea is that the smaller wings actually caused less drag than the large wings of an ostrich. However, it may just be that we have the wings incorrectly described in Titanis. My idea of drag could be completely incorrect also, but I will leave someone else to test that hypothesis or look up the literature on ostrich wing drag.