And evolutionary biologists keep looking for examples in nature, with meagre results:
Part of the problem is that the term species is notoriously difficult to define. A definition applicable to plants and animals won’t necessarily work for bacteria, and definitions applicable to living things won’t necessarily work for fossils. As of 2004, several dozen definitions were in use among biologists and paleontologists.3 The definition most often used by evolutionary biologists is the “biological species concept,” according to which species are groups of interbreeding natural populations that are reproductively isolated from other such groups.4
If species are defined this way, then in one sense speciation has been observed in the laboratory. Normally when two different species hybridize, either naturally or artificially, the hybrids are sterile because the maternal and paternal chromosomes are too dissimilar and cannot pair up in cell division. Occasionally, however, the hybrid undergoes chromosome doubling, or polyploidy. With matching sets of chromosomes that can undergo cell division, the hybrid may then be fertile and constitute a new species under the biological species concept. In the first decades of the 20th century, Swedish scientist Arne Müntzing used two plant species to make a hybrid that underwent chromosome doubling to produce hempnettle, a member of the mint family that had already been found in nature.5
Speciation by polyploidy is called secondary speciation to distinguish it from primary speciation — the splitting of one species into two. According to Douglas Futuyma, polyploidy “does not confer major new morphological characteristics…[and] does not cause the evolution of new genera” or higher levels in the biological hierarchy.6 So although secondary speciation by polyploidy has been observed in flowering plants, it is not the solution to Darwin’s problem. The solution would be primary speciation by variation and selection, which has not been observed.
Jonathan Wells, “Top Scientific Problems with Evolution: Speciation” at Evolution News and Science Today (February 17, 2022)
One way of attempting to demonstrate speciation is to seize on inconsequential genetic changes and inflate their importance:
A common refrain among biologists holds that the majority of Earth’s plant and animal species remain undiscovered. While many of those species inhabit narrow or hard-to-reach ranges, others may in fact be hiding right under our noses.
Take Ormyrus labotus, a tiny parasitoid wasp known to science since 1843. It has long been considered a generalist, laying its eggs in more than 65 different species of other insects. But a new study published today in Insect Systematics and Diversity suggests that the wasps currently called Ormyrus labotus are actually at least 16 different species, identical in appearance but genetically distinct.
It’s not unusual, especially with advancing genetic techniques, to discover “cryptic” species within one known insect species, but the number of those found within Ormyrus labotus underlines the importance of seeking out the world’s “hidden diversity,” says Andrew Forbes, Ph.D., associate professor of biology at the University of Iowa and senior author of the study.
Entomological Society of America, “Hidden diversity: When one wasp species is actually 16 wasp species” at ScienceDaily (February 16, 2022)
If that’s speciation, then the whole thing is waste of time. Even identical twins diverge genetically as trhey age.Should they be classed as separate species?
It’s a good thing Darwinism is part of an elite religion; it would not otherwise survive serious scrutiny long.
Wells reminds us,
In 2002, evolutionary biologists Lynn Margulis and Dorion Sagan wrote, “Speciation, whether in the remote Galápagos, in the laboratory cages of the drosophilosophers [those who study fruit flies], or in the crowded sediments of the paleontologists, still has never been directly traced.”13 So evolution’s smoking gun is still missing.
Jonathan Wells, “Top Scientific Problems with Evolution: Speciation” at Evolution News and Science Today (February 17, 2022)
Wait. Wasn’t otherwise refreshingly open-minded Lynn Margulis shouting on a Galapagos island during a Darwinfest, “I am definitely a Darwinist though.” Why was she? That wasn’t science; it was a cult.
The paper is open access.
You may also wish to read: A physicist looks at biology’s problem of “speciation” in humans