Evolution by definition is a change in a population of organisms over many successive generations. Evolution is responsible for all of the diversity on Earth we can see today, as evolution proposes a way for organisms to change over time and gradually speciate. The mechanism for evolution is natural selection which in a sense is an organism’s effectiveness at reproduction, so if an organism is more successful at reproducing more of its genes will make it into offspring and the species will shift towards those successful traits. If an organism is unsuccessful at reproducing or surviving it will be unable to pass on its traits and the species will shift away from those unsuccessful traits. Speciation which is the formation of two new species from one parent species is a direct result of evolution by natural selection and can occur in a number of different ways, like allopatric or sympatric speciation. Adaptation is a natural process, similar to natural selection in which the development or inheritance of new traits through sexual reproduction or asexual reproduction makes an organism more fit or better suited to live in that environment. Adaptation can lead a group of species to become more like its parent species or less like its parent species leading to further divergence of genetic traits and speciation, depending on environmental pressures. Further information regarding evolution can be found in Kishav’s very thorough blog post
The natural processes of evolution and adaptation has flowed continuously for millions of years with species responding to environmental pressures like competition, extreme weather events etc, until the rise of humans which greatly shift the environment and therefore environmental pressures. The rise of humans and the resulting exploitation of nature has created several distinctly new environmental pressures like, rapid habitat loss or fragmentation, excessive hunting, global warming and environmental damage caused by human actions (chemical spills etc.)
So human actions are having devastating affects on certain organisms, but this doesn’t mean that natural selection and evolution stop happening, in fact it’s the opposite, the various organisms and species of earth are now subject to more environmental pressures, which essentially creates a greater need for adaptation to occur, which inevitably leads to more organisms being selected against by the environment, and lower populations. This has lead to staggering amounts of vulnerable and endangered species.
So if such a large percentage of species are at risk of extinction, should humans interfere? Should we safe guard these species just to preserve the diversity of earth. Some estimates of rates of extinction suggest that current rates of extinction (sponsored by human activity) are more than 1000 times the natural rates extinction (100 extinctions per million species per year, as opposed to the natural rates of 0.1 extinctions per million species per year). This number may seem small but given that there are an estimated 8.7 million species on our planet without including bacteria, this adds up to something greater than 900 extinctions per year, so even if we protect certain species, we’re surely going to lose others. And even if we protect some of these species we would be interfering in the natural processes of natural selection, adaptation, speciation and ultimately evolution. This interference could prevent any new favourable traits from being inherited and the creation of any new species via adaptation and sympatric speciation, but if we don’t interfere we lose a great deal of diversity and may damage ecosystems. If this same situation is applied to humans however, where humans with genetic weaknesses like hereditary diseases are simply left to die because they don’t suit the environment it suddenly becomes very unfair and morbid.
While I am a supporter of the conservation of endangered species, this argument does pose several ethical questions about science in general: should we interfere in natural processes, should we alter ourselves to be better by researching things like the human genome, should the implications of our research be considered before actually conducting the research itself (like how the research of chemists like Ernest Rutherford was later used in the mahattan project.), what if the future implications cannot be forseen? Just because we know about things like heredity and how and why new traits are inherited, should we use this knowledge for our own benefit (designer babies?)? These are just some of the ethical questions that are brought upon by new discoveries in general, and while science is and was absolutely essential for the creation and improvement of the lives we live today, everything has a consequence.