Biological Evolution Right Before Our Eyes
I get annoyed often these days reading or hearing people express their devotion to science but treating science as if it were an authoritarian enterprise. Saying one should believe in the scientists as if they were some kind of high priests is contrary to the spirit of science. The spirit of science is pointing to the evidence.
Now, of course it is not always possible to double-check and personally understand everything that scientists have done, so some degree of trust in scientists is a practical necessity, but the spirit of science is to go as far in that direction as is at all reasonable. For biological evolution, there is a lot that can be done toward citing evidence that can be understood by most people—including by people who want to disbelieve in biological evolution. Cal Flyn’s June 3, 2021 Wall Street Journal article “When Pollution Drives Evolution” is a great help in that regard. No longer are light and dark colored moths the best examples of evolution in modern times.
Let me quote some highlights from Cal Flyn’s article, with passages separated by added bullets:
Since the late 18th century, the heavy industry that lines New Jersey’s Newark Bay has belched a thousand insidious contaminants into the waterway. Tanneries used sulfuric acid to strip hides, arsenic to preserve them and chromium to tan them. Hat makers used mercury nitrates to turn fur into felt. Later, factories produced polychlorinated biphenyls (PCBs), highly toxic oils and waxes once used as coolants and insulators, as well as the phenoxy herbicides known as Agent Orange and their noxious byproduct dioxin—one of the most toxic substances known.
In humans, these pollutants can cause every kind of cancer. In fish, PCBs alone are known to cause devastating deformities and developmental issues, including impaired fertility.
In 2016, a team of scientists at the University of California, Davis, genetically sequenced killifish from four contaminated harbors, including Newark Bay, and compared the genomes to those from uncontaminated sites. The pollution-tolerant populations had each evolved similar adaptations that rendered them up to 8,000 times more resistant to industrial pollutants, allowing them to live in water that would normally kill them.
This was evolution at a stunningly fast pace, given that the most harmful toxins were released in the 1950s and 1960s. And the killifish is not the only species to have managed this feat. The Atlantic tomcod in the nearby Hackensack River, for example, has also evolved a gene that makes it immune to the effects of PCBs.
… tawny owls in Finland are now changing their colors. Tawny owls come in two colorations, dark brown and pale gray. Records suggest that the proportion of dark owls is increasing, which researchers have linked to declines in snow cover.
Overfishing and overhunting have driven the evolution of smaller fish, which are better at slipping through nets, and tuskless elephants, since tusked species are more often killed for their ivory. In one South African national park, 98% of female elephants are now born tuskless. And that’s not to mention our ongoing arms races with pesticide-resistant insects, drug-resistant viruses and antibiotic-resistant bacteria.
There is no doubt that some disbelievers in evolution will remain unconvinced by even these examples, but I’ll bet that some will be convinced. And the mind and character of the one arguing for evolution is greatly enriched by making arguments based on facts such as these, rather than making an argument from authority.
On freedom of speech as opposed to authoritarian approaches to thought control, see: