Land to Sea and Sea to Land I don’t know why I thought this was so incredible, but I will tell you what I am talking about. We all know there were monster dinosaurs who walked the earth at one time, but scientists have just found something I would have never imagined. The desert in Africa has just yielded up something I would have to think was unbelievable. It was the fossil of a whale. A very ancient whale, but that is not why I found this so strange. What makes it strange was the fact the whale had four legs. It seems at one time whales walked the earth. I just can’t imagine that no matter how hard I try. They just don’t look like land creatures. I bet they weren’t very fast. It is amazing to note there were some animals who went from the sea, then to land, but eventually back to the sea. It wasn’t only the whales that used to walk on land. The dolphins were other creatures which crawled out of the sea and went to the land and over time went back to the sea. You really have to wonder how this works. It takes a long time, it is estimated it took about 350 million years for sea, land, sea conversions. Interestingly, it started for the back to the sea era when the great extinctions were taking place about 250 million years ago. It seems nature did this to save some species. Early dolphins had legs and could walk on land. Today the remains of the legs are still evident in pelvic bones that are rod shaped. One animal which is on land today is the elephant, but scientists wonder if it came out of the ocean at one time. The reason they do all this wondering is the fact it is so closely related biologically to the manatees and the sea cows. As of yet there is no way to know for sure. Scientists believe one type of animal is noted for going back and forth many times and it is still going on today. The animal is the snake. In the past some snakes had legs. They then went into the ocean and back to land several times. This is not true for all snakes however. I think most of us who picture seals in our mind’s eye see an animal with flippers sunning itself on a rock. Seals seem to be both aquatic and land capable animals. Scientists believe seals have been around for at least 15 million years if not longer. They had legs, but over time they some how changed into flippers and the seals hit the seas. Scientists believe they might have found the missing link which seals, sealions and walruses developed from. It is a species that lived in the arctic from 25 million years ago to 5 million years ago named Puijila darwini. One scientist said when discussing this animal he believes the animal was both adept at swimming and walking. For many years scientists have felt there had to be a common ancestor which the above animals developed from, but were unable to find it. Did you ever wonder what the first animal to walk on land was and where it happened? Scientists think they know the answer to this question. It was called an Ichthyostega. It is claimed it made it to Willie’s Hole in Scotland. The reason scientists believe this, is they found fossils which indicate this is true. I think most of you know what I am about to say, it is only true until an older fossil is found. I always have felt just because someone has the oldest example of something doesn’t necessarily mean it is truly the oldest and there isn’t an older example out there just waiting to be found. The fossils which were found were from 360 million years ago and the animals had 4 legs. We usually hear more about animals which came from the ocean and stayed on land rather than the ones which went from land to the ocean. One reason might be there are more of them that did it. Amphibians crawled out of the water and walked on the land, but they couldn’t really populate it very deeply. The reason for this was they had to stay near the water to lay their eggs. This was a severe limitation. Nature took over and the reptiles evolved from the amphibians. They were better equipped for living on the land. Some of the reptiles went to the oceans to live and the rest penetrated deep into the wilderness. Some developed wings and became able to fly, these were the pterosaurs. It is said contrary to belief birds did not develop from the pterosaurs. Some people believe just because pterosaurs flew, they were the ancestors of birds and they weren’t. People also believe they were dinosaurs and they were not, they were reptiles who lived around the same time as the dinosaurs. About 150 million years ago, there were two dinosaurs which were very bird like. They were the Archaeopteryx and Epidexipteryx. Some scientists believe the first birds could have descended from them. The problem is no one can be sure, so it is only an educated guess. About 230 million years ago tiny animals were in the trees. We know this because of the fossil record. They were in a world facing huge dinosaurs and were defenseless. I am always amazed any of them survived. They did however and eventually they became the animals we have today. But it wasn’t easy because the last dinosaurs lasted until about 65 million years ago. These tiny mouse sized creatures were survivors and once they had the opportunity to develop, they took over the earth. All along the evolutionary path there are missing links. The dictionary defines the term ‘missing link’ in this case as a hypothetical fossil form intermediate between two living forms, especially between humans and apes. But they exist between different species of animals also. Scientists want to be able to but out a series of fossils or skeletons from the beginning of one era to the present to show all the phases of evolution and it is very hard to do and even when it is accomplished, who can be sure it is correct? I have often said when you are collecting bones and assuming different creatures evolved from the set of bones before them, you are not really on solid ground. We know of many mistakes which were already made, but what about the ones we don’t know about?
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