Natural selection is extremely creative

2022-07-30 0 By

Life forms in the world are extremely diverse.The butterfly above is a hookworm, a butterfly that heralds spring early.With its delicate yellow wings, it is the best representative of the insect world, and this group of creatures known as “insects” is surprisingly diverse.The sheer number of life forms can sometimes seem overwhelming: we share a world with countless animals, plants and even more countless microbes, each seemingly well adapted to its particular lifestyle and environment.No wonder that for thousands of years most people believed that so many different creatures must have been created by a divine creator.During the 18th and 19th centuries, thinkers began to draw parallels between the complex mechanisms of living things and the design and construction of complex machines during the Industrial Revolution.Such comparisons often reinforce religious beliefs: how could such intricate creatures have emerged without the painstaking efforts of a super-intelligent designer?In 1802, the Reverend William Paley illustrated this line of thinking with a vivid example.He asks you to picture this: You’re out for a walk and you find a pocket watch by the side of the road.As soon as you open the dial and see the intricate mechanics that are clearly designed to keep track of time, he said, ‘it’s bound to convince you that the watch was made by an intelligent creator.’Paley argues that the same logic must apply to the delicate mechanics of life.We now know that complex life forms with a purpose can emerge without any designer, thanks to natural selection.Natural selection is the creative process that has created us, and the vast array of life forms around us: from millions of species of microbes to shovel-nails with fearsome jaws, lion’s mane jellyfish with 30-meter tentacles, pitcher plants that trap bugs with flux-filled traps, gorillas with opposable thumbs, and us.Evolution by natural selection has never deviated from the laws of science or the supernatural to produce ever more complex and diverse creatures.Over billions of years, different species have emerged, explored new possibilities and interacted with different environments and other creatures, and as a result, morphologically bizarre beyond imagination.All species — including us — are in a state of constant change, eventually heading towards extinction or evolving into new species.At the top of the evolutionary tree was Charles Darwin, the 19th century naturalist who sailed around the world on the small Royal Navy ship HMS Beagle, collecting plant, animal and fossil specimens.Darwin eagerly gathered observations in support of evolution and eventually came up with a wonderful idea — natural selection — to explain how everything evolved.He wrote all his thoughts in the Origin of Species, published in 1859.Of all the great ideas in biology, evolution should be the best known, if not always the best understood.Darwin was not the first to suggest that life evolved over time.As he points out in The Origin of Species, Aristotle had argued that certain body parts of animals could appear or disappear over long periods of time.In the late 18th century, jean-Baptiste Lamarck, a French scientist, went a step further, suggesting that different species could be related.He proposed that species change gradually as they adapt, and that their form changes with their environment and habits.Lamarck famously argued that giraffes got their long necks because each generation of giraffes raised their heads to eat the leaves on the taller branches of trees, and somehow passed on the laborious habit to their offspring, who then had longer necks.Now, Lamarck’s ideas are sometimes underestimated because he didn’t get the details of evolution right, but he deserves a lot of credit for being the first scientist to explain evolution in a comprehensive way, without even mentioning why it happened.Lamarck, of course, is not alone in thinking about evolution.Even in Darwin’s own family, his grandfather Erasmus Darwin was another early and enthusiastic proponent of evolution.He carved his Latin motto on his carriage: E conchis omnia, meaning “All from the shell,” to spread his idea that all life had evolved from simpler ancestors, such as the seemingly unshaped mollusk inside the shell.However, he had to remove the inscription from his carriage after the vicar of Lichfield Cathedral accused him of “turning his back on his creator”.Erasmus had no choice, for he was an established doctor, and he knew that if he did not do so, he risked losing his powerful, respected, and richer patients.Charles Darwin explained evolution in a more scientific and systematic way, and in a more traditional way, confined to prose rather than poetry.He has collected a large number of fossils and animal and plant specimens from home and abroad, accumulating massive data and observation and research records.The data he crunched provided strong evidence for the view shared by Lamarck, his grandfather and others that organisms do evolve.But he did more than that when he came up with the evolutionary mechanism of natural selection.He connected all the dots and showed the world how life evolved.