Life's Rocky Road: The History of Life on Earth

The Lecture Life’s Rocky Road: The History of Life on Earth was given this past Thursday by Nigel Hughes. The lecture’s theme was that even though we cannot travel into the past to observe things as they actually occurred, we can use things occurring in the present to understand the past. Hughes explained this by pointing out that the number of tree rings on a tree trunk is equal to how old the tree is. The age of a rock can be found by examining the type of fossils that are found within it. Hughes then went on to list the earliest forms of life that we currently know of. The earliest fossils that have been uncovered are 3400 million years old. However, these fossils are on a microscopic scale and cannot be seen with the naked eye. Since then, fossils of other types of bacteria and organisms have been found that help explain the process of growth in plants and animals. An organisms’ fossil estimated to be 570 million years old, is thought to be a very early example of sexual reproduction. It is still unknown whether the organism was a plant or an animal, however it was large enough to be seen with the naked eye. Those that discovered the organism believe it reproduced sexually because of the fossils that were found. The fossil showed groups of large spores next to a cluster of smaller spores. The larger spores seem to represent the older generation while the smaller ones appear to represent the younger generation. Hughes lightly touched on the fact that organisms on earth have extremely similar genes even those with drastically different body types. This is evidence for our common ancestry with other organisms. The lecture concluded with the topic of anthropogenic global warming. The temperatures on earth are rising at an alarming rate and promise to continue to do so. Although all we have to do to continue our run on earth is to adapt, the reality is that most organisms do not adapt in time. Only time will tell whether humans will survive or not.