Recently Sirenians, or sea cows, have been stirring the pot of evolution in the biological world. Today, there are only four known species of sirenians. The closest living relative to the sea cow is the proboscidean, or elephant. The sirenians fossil record is much more diverse than most. This is due to the fact that the sirenians played a vital role in one of the greatest evolutionary steps in the history of our world. The transition from primarily sea-dwelling animals to primarily land-dwelling animals is seen through numerous transitional forms in the fossil record. Morphologically, they are very similar to whales. Also, this transitional process had been thought to have had a relatively short time period associated with it. I think this fact in itself is very interesting in the evolutionary history because people always associate evolution with long time periods of little change, when that is often not true. The sea cow is just another example of this very principle.
As I read that part of the article I found, I thought about why this time period was so short, maybe there was a great need for these sea-dwellers to break land. The later forms still retained a small femur, and yet the morphology in the modern day serenians is very similar to that of a while with the streamline body and horizontal tale fluke. This was interesting to me because in the last few units we have been talking a lot about common ancestry and how closely related different species in the same, or different orders are. Also, I think that throughout more recent years, with all of the technological advancements in the scientific realm, it has become more and more confusing, and yet still just as important to use the new technology to help us distinguish from what we thought in the past and what is now actually more accurate.
Also, when I read this, my mind automatically thought of the snake becoming a land animal scenario that we watched in the video earlier this week. It’s so interesting that evolution has its own system to weed out what doesn’t work and benefit those that are better suited. After watching this video and reading this article regarding the transition of animals from primarily sea-dwelling to primarily land-dwelling, I began to wonder what may have caused this drastic adaptation over many generations. Maybe the competition for find different food resources prompted this? Was it driven by predatory threats from an influx of a new species in the area? Or could this have been caused by competition to find a better suited, or more appealing, mate? We probably will never know what was going on in the sirenians, or snakes mind when something spiked their curiosity to a world above, but we can utilize our resources today and take advantage of what evidence we have today to try and piece together the history of our world from a biological standpoint.