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Is a vast variety of new cichlid species in ten million years a “burst”?

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Then why is it wrong to talk about the Cambrian explosion?:

A recently published study in Nature offers a new wealth of data on Lake Tanganyika’s cichlids and uses it to outline the wild ebb and flow of evolution for these fish, which diversified from one common ancestor to an astonishing 240 or so cichlid species in less than 10 million years.

That’s a very small amount of time for so many species to evolve, said Walter Salzburger, an associate professor at the University of Basel’s Zoological Institute and senior author on the study. And this process wasn’t gradual or random — the data reveals that these cichlids evolved predominantly in bursts. “It’s still surprising how clear and distinct these pulses of accelerated evolution are,” Salzburger said.

Elena Renken, “New Fish Data Reveal How Evolutionary Bursts Create Species” at Quanta

Bursts? How dare they use such language!

A friend has noticed that 10 million years—about the same extent of time as the initial Cambrian explosion—is regarded as “a very small amount of time” for mere speciation events.

But now, the term “explosion” has become politically incorrect usage to describe the Cambrian because shut up:

See: At Geological Society of America’s house rag: QUIT calling it the Cambrian Explosion! Sorry, guys. The Cambrian is a bit like quantum theory. Anyone who ISN’T flummoxed by it doesn’t understand it. Now comes the punch line: “We suggest, as an alternative to “Cambrian explosion,” the Great Cambrian Biodiversification (GCB)…” Sure, that’ll catch on. It sounds like a large animal vet’s description of an elephant’s bowel problems.

Comments
I've seen claims of cichlid fish "rapid evolution" before and wondered just how different are these "species"? Perhaps they are like Darwin's finches; merely small adaptations by shifting allele ratios for local conditions. Can these different cichlid "species" reproduce together with fertile offspring? Are they simply different colour patterns like guppies in a fish tank?Fasteddious
December 3, 2020
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In fairness, bursts are a characteristic of mathematically random processes. When you see a set of events that seem to be evenly distributed across space or time, it's a pretty good sign that some kind of intelligence or intelligently applied mechanism has smoothed out the distribution. When you see spatial clusters or temporal 'streaks', it's a pretty good sign of mathematical randomness.polistra
December 2, 2020
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