Showing posts with label Darwin. Show all posts
Showing posts with label Darwin. Show all posts

Wednesday, July 28, 2021

A NEW ECOLOGY

The roof of the California Academy of Sciences (CAS) in San Francisco’s Golden Gate Park is a garden that looks odd but merges naturally with the park surrounding it. Having a wide variety of plants, the roof attracts pollinators and provides insulation for the building beneath it.

 

https://www.calacademy.org/exhibits/living-roof

When we drove along a large highway in Canada several years ago we were surprised by passing beneath a huge overpass with plants growing on it. It turned out to be a corridor for wildlife, which had been constructed so that moose, deer, and other animals could cross the highway safely. Like the CAS roof, the overpass was a human-made structure that contributed to the natural biome rather than interfering with it.

The Dutch biologist Menno Schilthuizen has pointed out that evolution is occurring quickly all around us. For instance, some spiders have evolved to be attracted to the lights where insects gather, and starlings have even changed their wing shape in a way that allows them to flee from some urban dangers. As every high school biology student knows, peppered moths rapidly evolved in the nineteenth century, becoming dark to match the sooty backgrounds in their industrialized English environments. Parakeets in Paris are of two distinct genetic types that could mix but do not; like many other animals, they have evolved to remain in slightly different habitats.

Many of Schilthuizen’s examples sound more like variations in species than true evolution, but his point that changes are occurring swiftly within organisms in urban and natural environments cannot be denied. Surprisingly, he is hopeful that we can work with many of the changes rather than resisting them.

Ever since the sixties, I have agonized over human alterations to our natural environment. Even our wonderful national parks and wilderness areas have suffered from pollution, urban sprawl, mining, and other obscenities. In traveling in a motorhome throughout North America I have watched the crumbling of many ecosystems. Conservation of current natural resources has seemed like environmentalists’ only worthwhile goal. Perhaps Schilthuizen has the right idea. If some organisms evolve in a way that benefits them and their surroundings, we can encourage them. If some become extinct, their replacements may be worth preserving. Those of us who mourn the loss of familiar plants and animals can try to imagine future ecosystems and design appealing cities for them. We cannot stop evolution, but we can search for new ways to live with it.

 

Copyright © July 25, 2021 by Carol Leth Stone (a.k.a. RovinCrone)

Thursday, May 23, 2013

THE NEANDERTHALS AMONG US



You never know what you may see from an RV window. The South seems especially rich in remarkable sights: One day as we drove along, minding our own business, we saw a huge billboard advertising a dinosaur museum, and we slowed down to check it out.

As it turned out, the museum was too expensive for us—$24 per person, even for us senior citizens. Good grief! For that price, we could have visited a world-class paleontology museum such as the Field Museum of Natural History in Chicago, or the American Museum of Natural History in New York. More important than the egregious admission price, the museum was anti-science; it was a thinly disguised exhibit about special creation, or the creation of living things as presented in Genesis. We saw no benefit in supporting it, and kept driving.

Some scientists believe God created life; others do not. What nearly all of them agree on is that living things have evolved (changed gradually) since they first appeared on Earth, branching in various directions to form the millions of species that have lived and died over the eons. Evidence from paleontology, anatomy, genetics, embryology, physiology, and  other areas of biology all show similarities among organisms that make sense only if they evolved gradually .

The comic strip Alley Oop is delightfully entertaining. (Oop is a time-traveling Neanderthal who rides through a Carboniferous forest on a dinosaur, battles other cavemen, and so on.) The strip is a pleasant fancy, but of course it is nonsensical. The dinosaurs were wiped out 65,000,000 years ago, millions of years before the Neanderthals appeared. Creationists, though, have tried to insist that all living things were created within 6,000 years, and so humans and dinosaurs actually co-existed. In a hilarious exhibit at one creationist museum, fossils appear to show a dinosaur eating a person.

The creationists have been ridiculed for years, and are thin-skinned enough to have gone through a sort of evolution themselves. Now they call their ideas “intelligent design,” a supposedly scientific theory that is less obviously religious. However, they dodge the question of how there can be a design unless there is a designer. For that matter, what would unintelligent design be?

Back in 1958, just before the centenary of The Origin of Species by Natural Selection, a famous scientist wrote that “a hundred years without Darwinism are enough.” He was appalled that there was still any opposition to a theory that was accepted by the scientific community. And that was more than 50 years ago! There have been amendments to Darwin’s theory of evolution—punctuated equilibrium and the molecular structure of DNA, for instance—but the basic idea of evolution by natural selection has stood the tests of time and of challenges from naysayers.

In recent years researchers have shown that Neanderthals interbred with some groups of modern humans, which means that most of us have some Neanderthal genes. In another sense, though, Neanderthals are all around us—denying evolution, denying climate change, denying science. Will this denial continue for another hundred years? Or will we say this is already more than enough?