This is so cool! Laboratory synthesis of an independently reproducing vertebrate species. This might take some explaining, so bear with me (it's worth it!)
Firstly, an introduction to chromosome numbers ('ploidy'). You and I have two copies of each of 23 chromosome - we say we are DIploid. Gametes (sex cells - sperm and eggs) usually have one copy of each chromosome; they are HAPloid.
Now, out in the deserts of New Mexico, there are some species of lizard that reproduce parthenogenetically. This means that the females produce genetically identical copies (clones) of themselves. These lizard populations are all female and there is no sex. These lizards with a bizarre reproductive strategy are the result of hybridisation between two sexual species. Many (5 of 7) of these species are TRIploid: they have 3 copies of each chromosome. These triploid species are thought to have arisen through hybridisation (a single mating) between a male from a sexual species and a female of a diploid, parthenogenetic species.
Normally, offspring from crosses between different species are sterile (e.g the mule - a horse x donkey cross), so the fact that these offspring can reproduce is weird enough, especially since it has happened so many times and involves the total loss of males and sex, but what happens next is absolutely unprecedented and astounding. The authors of this paper crossed diploid males with one of the triploid, female only species (although these don't ordinarily have sex, the females are still capable). The result is a TETRAploid lizard (four copies of each chromosome) which can reproduce parthenogenetically and is isolated from both parent species. This was repeated to produce 4 lineages. Voila! Instant new species, made in a laboratory!
Life really is stranger than fiction.
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