Evolution is often described as a process full of chance and randomness.
But a new study suggests that it may be more predictable than we once thought.
Scientists have discovered that evolution has been using the same genetic “tools” for more than 120 million years to create similar patterns in different species.
An international team of researchers, led by scientists at the University of York and the Wellcome Sanger Institute, studied butterflies and moths from South American rainforests.
These species are not closely related, yet many of them have very similar wing color patterns.
These patterns act as warnings to predators, especially birds, signaling that the insects are toxic or unpleasant to eat. This phenomenon is known as mimicry.
The researchers wanted to understand how these different species developed such similar appearances.
After studying seven types of butterflies and one day-flying moth, they found something surprising. Despite being distantly related, all these species used the same two genes, called ivory and optix, to create their wing patterns.
However, the genes themselves were not changing much. Instead, evolution worked by altering the “switches” that control when and where these genes are turned on or off. These switches are parts of DNA that regulate gene activity.
By tweaking these switches, different species were able to produce similar color patterns without changing the genes directly.
The study also revealed another interesting detail. One of the moth species used a slightly different method, flipping a large section of its DNA in a process known as an inversion.
Even so, this method was very similar to a genetic trick used by one of the butterfly species, showing that evolution often finds comparable solutions to the same problem.
According to lead researcher Kanchon Dasmahapatra, this is an example of convergent evolution, where unrelated species independently develop similar traits.
While this is common in nature, it is rare for scientists to understand the exact genetic basis behind it. This study shows that evolution can follow the same path repeatedly, especially when there is a clear survival advantage.
The reason these patterns are so widespread is simple. Predators like birds learn to avoid certain colors that signal danger. If one species already uses a successful warning pattern, it benefits other species to copy it. As explained by researcher Joana Meier, these shared color patterns are effective because they are easy to evolve using the same genetic system that has been conserved over millions of years.
The findings, published in PLOS Biology, suggest that evolution is not entirely random. Instead, it often reuses successful genetic solutions. This predictability could help scientists better understand how species might adapt to environmental changes, including climate change, in the future.
Source: KSR.
