Innovation and Speciation: attributes causing (Evolution)

by David Turell , Saturday, August 26, 2023, 20:10 (245 days ago) @ David Turell

Climate and physical separation:

https://phys.org/news/2023-08-crowd-sourced-science-species-space.html

"...some places on Earth have far more species than others. In fact, the distribution of species across the globe follows a curiously consistent pattern: generally, there are more species closer to the equator and fewer as you move towards the poles. This "latitudinal biodiversity gradient" can be observed across many different groups of organisms over time.

"One possible explanation for the presence of more species closer to the equator is that changes in climate from the equator to the poles affects the ability of new species to evolve—a process called speciation.

***

"The fall webworm is a moth found from Mexico to Canada (a range of almost 4,000 km) whose caterpillars have either black or red heads. While this might seem like a subtle difference, caterpillars with these different colors seem to have different behaviors and appear at different times of the year, and genetic studies suggest that they are evolving into different species.

"This moth is also found throughout vastly different climates, which allowed us to explore how latitude and climate might be affecting their ability to turn from one species into two.

***

"The process of speciation occurs when two groups of organisms belonging to the same species are separated by a barrier that prevents them from reproducing. The most well-known way that this can occur is through a physical barrier between the groups, like a mountain range or a highway.

"For the fall webworm, the barrier causing them to become two different species is time. In general, moth species only appear and reproduce during the summer, and when they do, they breed for only a few weeks, at most.

"The red-headed and the black-headed fall webworms tend to emerge and reproduce at different times during the summer, and this time gap creates a barrier that is causing them to become two different species.

"Summers toward the equator tend to be much longer, so the fall webworms go through more life cycles in a year compared to northern populations, which are only able to breed once during short summers. If the red-headed and black-headed fall webworms closer to the equator have more flexibility in when they can breed, they may be able to avoid each other in time better, making speciation more effective.

***

"Using all these observations, we found that in more northerly regions with short summers, the red-headed and black-headed fall webworm caterpillars were forced to breed at the same time and had more similar coloration. This suggests that more breeding was occurring between the groups, and they looked and acted more like a single species.

"However, in their southern range, the black- and red-headed caterpillars were able to separate their generations more and had less similar coloration, meaning they may be further along in the process of becoming two species.
We found that differences in climate from the equator to the poles affect how well species can evolve when time is the barrier, mirroring the latitudinal biodiversity gradient. In short, climate can change how easily species form in the first place.

"There are approximately 2.1 million classified species on Earth, and over one million of these are insects (with many millions more undiscovered), making them the most diverse animals on the planet.

"Species are migrating, either as invasive species coming to new places, or moving poleward to escape warming climates."

Comment: unfortunately, all this tells us is what drives speciation, not how DNA is edited to design the new species.