Category Archives: Evolution

Life on Earth has evolved from the simple to the complex. I will assume the reader is familiar with at least the basic concepts of Darwin’s theory and of evolution and biology in general. Darwin’s theory of natural selection accounts for the survival of successful life forms and for the increase in complexity resulting from such selective pressures as he describes. Such selective pressures allow for more and more complex organisms and symbiotic relationships that may or may not eventually evolve to be a single organism. For example, mitochondria are assumed to have been “eaten” whole by certain free cells and instead of being digested, the mitochondria survived in the host cell, obtaining nutrients from the cell while giving energy to the cell in return. This would be an example of how two different organisms combined to become one. Was this relationship a symbiotic one at first before the ultimate … Continue reading →

A news headline that the tree line was moving north toward the arctic inspired this post. Comments raged between people who despise big oil for causing environmental meltdown, and those who say it’s just part of a natural process. Both sides pick factoids from the internet to support their dogmatism. Arguments about global warming aside, the fact is that humans have directly and indirectly caused massive ecosystem changes. The ecosystems of the planet will never be the same. We can never make North America, for example, like it was 300 years ago when buffalo roamed freely. We can never remove imported species from the Great Lakes. In the same way if the caribou are threatened by the tree line moving north they will likely not be able to survive as well as they survive now. The reason is that they are not free to move. Man is here to stop … Continue reading →