Some creatures survive the most extreme conditions. Slitted nostrils and fatty humps sustain camels' treks through extreme Saharan desert heat. Extra red blood cells help guanacos survive the low oxygen in the high Andes. Strong jaws and a flexible skull let the rat survive so well it has become a pest. Cockroaches have supersensitive antennae and an extra abdominal brain. A male emperor penguin protects a newly laid egg from frigid air by balancing it on his feet and covering it with warm skin. The cold-blooded New Zealand weta cricket freezes in winter and its systems shut down until spring thaw. Amazing survivors!