A full-grown T. rex was probably the most fearsome sight of the Cretaceous. But as with the teenagers of many species, adolescent T. rexes inspired their own form of terror. Fast and light, they could catch prey their parents couldn't. The T. rex was "basically king of its environment from the get-go," said Holly Woodward, an associate professor of anatomy and paleontology at the Oklahoma State University Center for Health Sciences. She and her colleagues' findings suggest that young T. rexes responded to the amount of resources available, growing quickly when food was plentiful, and stopping when times were lean. The variable growth rates allowed teen tyrannosaurs to terrorize the landscape just as effectively as their adult counterparts. While some researchers have argued that small tyrannosaurus remains were of a separate species, the team said their evidence suggests they were likely not fully grown.

Scientists sequence cobra genome

Scientists have sequenced the genome of one of the deadliest snakes in the world, the Indian cobra, the Naja naja. In Nature Genetics, researchers reported finding 12,346 genes expressed in the venom glands, 139 of which were toxin genes. Then they narrowed to 19 the ones responsible for a wide range of symptoms in humans, including heart-function problems, paralysis, nausea, blurred vision, internal bleeding and death. Scientists can now begin to use recombinant protein technologies to generate new anti-venoms.

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