Hi Al
I have specific references for some of them.
Stanley's 1979 book "Macroevolution" on pages 40-47 mentions a number of examples of recent speciation, including the Hawaiian moths (not fruit flies, my memory was false) and copepods (not fish) in reservoirs. The Hawaiian
moths belong to the endemic genus Hedylepta. Five species (plus others not described at the time) form a clade of banana-eating moths. Bananas were introduced by humans about 1,000 years ago. The non bananaiverous members
of the genus feed on palms, although will also feed on bananas. These species must have evolved since humans introduced the plant. The planktonic copepod Cyclops dimorphus appeared in the Salton Sea about 30 years after it
formed. Its closest relatives would be riparian species.
The sub-antarctic rodents were mentioned to me by R. J. Berry (editor of Science and Christian Belief) who did a lot of the basic work on them. Some have different chromosome numbers to the parental mice. A similar example
is provided in Stanley by the Faeroe island mouse (Mus musculus faeroensis) which has, depending on the author, been placed in a separate sub species or species. It was introduced 250 years ago.
The Australian fruit flies I heard about on an ABC radio program. a friend who worked for the Queensland museum told me about the adaptation of local arthropods to Pinus radiata.
A great many observed examples of speciation in the wild and laboratory can be found at <http://www.talkorigins.org/faqs/faq-speciation.html> and <http://www.talkorigins.org/faqs/speciation.html>. Examples there include:
The evening primrose (Oenothera lamarckiana), which has a chromosome number of 2N = 14. Variants have been observed which have a chromosome number of 2N = 28. These are unable to breed with O. lamarckiana and have been named
O. gigas.
The Kew Primrose (Primula kewensis) was produced by artificially crossing Primula verticillata and P. floribunda to produce a sterile hybrid. Polyploidization occurred in a few of these plants and produced fertile offspring.
The process has been observed to occur spontaneously on a number of occasions.
The genus Brassica contains several important (though not always popular) food plants, including kale, cauliflower, broccoli. The different species of Brassica appear to be the result of artificially selected hybrids, B.
carinata (n = 17) may be recreated by hybridizing B. nigra (black mustard, n = 8) and B. oleracea (cabbage), B. juncea (n = 18) may be recreated by hybridizing B. nigra and B. campestris (turnip, n = 10), and B. napus (n =
19) may be recreated by hybridizing B. oleracea (cabbage) and B. campestris.
Hope this helps
Jonathan
Mccarrick Alan D CRPH wrote:
> Jonathan Clark wrote:
>
> >JC. This is understating the evidence, which goes far beyond toxin resistance or even industrial melanism.
> >Speciation has been observed in historic times when new ecological niches have been created. Example I
> >recall include as introduced rodents in sub-Antarctic islands, appearance of indigenous arthropods to feed on >introduced plants in Australia, similar appearance of fruit flies to feed on bananas in Hawaii, and speciation
> >events of fish adapted to flowing waters to tranquil waters. The changes involved in these examples included
> >in feeding strategies, limb and jaw morphology, and chromosome number.
>
> Jonathan:
>
> Could you give some references for these items.
>
> Al McCarrick
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