And just in time to save intelligent design, passage found in Bible proves Whale/Hippo Hybrid was in plan all along. Quote God: “Whale/Hippo hybrid mammals will be superior to the modern automobile circa 2006. They will get 75 miles per gallon. And when I say gallon I mean cubic ton of seawood. Golly gee, take a gander at the chompers on my whip!”
“Whales are warmblooded animals like we are—that has been known for a long time,” Gingerich explains. “Yet they’re so different from other warmblooded, furry things that it’s been a mystery, both how they came to live in the sea and what ancestors they might have come from on land.”
“More than 50 million years ago the ancestors of whales and dolphins were four-footed land animals, not unlike large dogs….
“In findings to be published this week in the Proceedings of the National Academy of Sciences, scientists say the gradual shrinkage of the whales’ hind limbs over 15 million years was the result of slowly accumulated genetic changes that influenced the size of the limbs and that these changes happened sometime late in development, during the fetal period.
“However, the actual loss of the hind limb occurred much further along in the evolutionary process, when a drastic change occurred to inactivate a gene essential for limb development. This gene – called Sonic hedgehog – functions during the first quarter of gestation in the embryonic period of the animals’ development, before the fetal period.
“In all limbed vertebrates, Sonic hedgehog is required for normal limbs to develop beyond the knee and elbow joints. Because ancient whales’ hind limbs remained perfectly formed all the way to the toes even as they became smaller suggests that Sonic hedgehog was still functioning to pattern the limb skeleton.
“The new research shows that, near the end of 15 million years, with the hind limbs of ancient whales nonfunctional and all but gone, lack of Sonic hedgehog clearly comes into play. While the animals still may have developed embryonic hind limb buds, as happens in today’s spotted dolphins, they didn’t have the Sonic hedgehog required to grow a complete or even partial limb, although it is active elsewhere in the embryo.
“The team also showed why Sonic hedgehog became inactive and all traces of hind limbs vanished at the end of this stage of whale evolution, said Cohn. A gene called Hand2, which normally functions as a switch to turn on Sonic hedgehog, was shown to be inactive in the hind limb buds of dolphins. Without it, limb development grinds to a halt…
“Now I even admit the possibility that hippos are a side line of artiodactyls that might be closer to the whales than any other living animals,” he says.
Gingerich had expected that the feet and hands of the older whales would be more like those of land animals than they turned out to be. While they are more fully developed than those of Basilosaurus, they still are not designed for walking long distances.
“It’s clear that these animals could hitch their way out of water and back in like sea lions do today, but they were more aquatic than I realized,” says Gingerich. The size and shape of their bones suggest that they had webbed hands and feet and probably also used their tails to propel themselves through the water.
“The DNA that animals carry in their bodies today gives us a better picture of the past than we might have thought it did. If we can make reliable inferences from animals that are living today, we can learn a lot about the past much faster. These techniques will never replace paleontology, but they will complement it and expand on what we can competently infer.”
Links to press releases… New fossils suggest whales and hippos are close kin … How ancient whales lost their legs, got sleek and conquered the oceans
hippo-notic!