A few years ago, I have seen a documentary film about a plant in
Hawaii, I could not remember it's name, but it looked like a weed that
most people would not bother about it. This plant has quickly spread
to locations at various altitudes with climatic differences, and
therefore each plant has evolved into a different variation that
superficially looked very different from the original plant. I also
recall that the diverged species could be crossbred, because there was
not enough time to make genetic divergence, but I did not see how the
hybrid species would look like.

Maybe the data I'm providing is not enough to give a hint to the
species I'm inquiring about, but I can give you an example from the
world of cacti, with which I'm much more familiar: Most cacti can be
grafted on other types of cacti, because they are closely related,
although they look quite different: The ribbed structure of ferocacti,
the radiating shape of Mamillarias, the star-shaped Ariocarpus, and
the columnar Quiabentia which still carries leaves. If we
crosspolinate two different cacti and obtain viable seeds, how would
the hybrid look like ? Is there an example of such a plant I would
find i the market ?

In article ,
(Gabriel) wrote:
A few years ago, I have seen a documentary film about a plant in
Hawaii, I could not remember it's name, but it looked like a weed that
most people would not bother about it. This plant has quickly spread
to locations at various altitudes with climatic differences, and
therefore each plant has evolved into a different variation that
superficially looked very different from the original plant. I also
recall that the diverged species could be crossbred, because there was
not enough time to make genetic divergence, but I did not see how the
hybrid species would look like.

Maybe the data I'm providing is not enough to give a hint to the
species I'm inquiring about, but I can give you an example from the
world of cacti, with which I'm much more familiar: Most cacti can be
grafted on other types of cacti, because they are closely related,
although they look quite different: The ribbed structure of ferocacti,
the radiating shape of Mamillarias, the star-shaped Ariocarpus, and
the columnar Quiabentia which still carries leaves. If we
crosspolinate two different cacti and obtain viable seeds, how would
the hybrid look like ? Is there an example of such a plant I would
find i the market ?

This reminded me of the tale we heard at University years ago about
the Russian attempt to create a useful vegetable combination by
crossing a cabbage with a raddish. Unfortunately, it ended up with
cabbage roots and raddish leaves. :-)

Nevertheless, _Raphanobrassica_ exists as a fertile species following
doubling of the chromosome set.

Here's some detail on it's origin stolen from
http://www.biologie.uni-hamburg.de/b-online/e12/12c.htm

quoting
In 1928, G. D. KARPETSCHENKO (Institute of Applied Botany, Detskoje
Selo near St. Petersburg) produced a new species: Raphanobrassica (2n
= 36) by crossing Raphanus sativus (2n = 18; radish) and Brassica
oleraceae (2n = 18; cabbage). It seemed at first as if the hybrid was
sterile but after numerous experiments, a fertile specimen could be
found. Fertility was preceded by the doubling of the chromosomal set.
Accordingly, we have the following combinations: 9+9= 18 (sterile) and
18 x 2 = 36 (fertile).
/quoting

The above URL will take you to a page titled "The Formation of New
Species" which gives several such examples (and has a link to a neat
computer generated analysis of the lines of descent of 63 species of
_Nicotiana_ FWIW).





Cheers, Phred.

--
LID

There are hundreds of examples of "wide" crosses in Cactaceae. The so called
"Epiphyllum" hybrids are actually complex crosses between Heliocereus,
Nopalxochia, Disocactus, Selenicereus, and Hylocereus but rarely are the
true Epiphyllum species used other than day blooming E.crenatum. Hybrids are
usually intermediate in appearance between the parents but there are
exceptions, especially when one of the parents is polyploid.


Gabriel wrote in message
om...
A few years ago, I have seen a documentary film about a plant in
Hawaii, I could not remember it's name, but it looked like a weed that
most people would not bother about it. This plant has quickly spread
to locations at various altitudes with climatic differences, and
therefore each plant has evolved into a different variation that
superficially looked very different from the original plant. I also
recall that the diverged species could be crossbred, because there was
not enough time to make genetic divergence, but I did not see how the
hybrid species would look like.

Maybe the data I'm providing is not enough to give a hint to the
species I'm inquiring about, but I can give you an example from the
world of cacti, with which I'm much more familiar: Most cacti can be
grafted on other types of cacti, because they are closely related,
although they look quite different: The ribbed structure of ferocacti,
the radiating shape of Mamillarias, the star-shaped Ariocarpus, and
the columnar Quiabentia which still carries leaves. If we
crosspolinate two different cacti and obtain viable seeds, how would
the hybrid look like ? Is there an example of such a plant I would
find i the market ?

Sounds like the silversword alliance. Yes, there was a documentary on this.
This plant group is mentioned in General Botany books as an example of
adaptive radiation. Judy Kelly

From the University of Hawaii website --
http://www.botany.hawaii.edu/faculty...ilversword.htm
"Members of the tarweed subtribe (Madiinae) of the sunflower tribe
(Heliantheae) of the aster family (Asteraceae), the Hawaiian silversword
alliance consists of about 30 species in three genera (Argyroxiphium,
Dubautia, and Wilkesia). The species exhibit an extraordinary range of
anatomical, morphological, and ecological adaptations but are exceedingly
closely related as judged by data from biosystematics and molecular studies.
The evidence favors the conclusion that all of this diversity evolved from a
single ancestor that colonized Hawaii by way of long-distance dispersal from
North America. More information on adaptive radiation, hybridization, and
evolution of this group is linked here. For further information and photos
related to individual species, click on a genus below. "



"Gabriel" wrote in message
om...
A few years ago, I have seen a documentary film about a plant in
Hawaii, I could not remember it's name, but it looked like a weed that
most people would not bother about it. This plant has quickly spread
to locations at various altitudes with climatic differences, and
therefore each plant has evolved into a different variation that
superficially looked very different from the original plant. I also
recall that the diverged species could be crossbred, because there was
not enough time to make genetic divergence, but I did not see how the
hybrid species would look like.