The researchers wanted to explore why only some fish hybridize between species. But they found something quite dramatic:
After deciding to focus on “one of the most charismatic and iconic groups of coral reef fishes”, the marine angelfish, they found that 42 species—nearly half of all known species of marine angelfishes—create hybrids.
“This is among the highest incidences of hybridisation in coral reef fishes,” Mr Tea said.
“We also found that hybrids are frequently produced even between angelfish species that are distantly related to each other; some separated by over 10 million years in evolutionary time.”…
Other hybrids were found between species with over 12 percent pairwise distance in mitochondrial DNA. Pairwise distance is a measurement of differences in pairs of DNA sequences.
“This genetic separation is quite astounding, considering that hybrids are rarely reported between species that share more than 2 percent in genetic distance,” Mr Tea said. “Though coral reef fish hybrids are common; they are usually formed by closely-related species.”University of Sydney, “Angels in disguise: Angelfishes hybridize more than any other coral reef species” at Phys.org
Probably, they ain’t seen nothin’ yet.
See also: The “Sturdlefish” Is The Offspring Of Sturgeon And Paddlefish—Separated By 184 Million Years’ Evolution