24 Oct 2002 03:35:16 GMT mel turner wrote:

In article , wrote...
[snip]

As far as I know the majority view is that Lycopersicon is an
independent
genus. However it certainly is not cast in stone. There have been, and
likely still are, those who regard the tomato and potato as belonging to
the
same genus

Indeed, that is the current classificatory trend. The tomato group
is nested very deep in a much larger _Solanum_ clade. It would be hard
to recognize it as a separate genus [doing so would seem to require
breaking the rest of Solanum up into many small genera]. Recent
researchers include not only tomatoes but also the "tree tomato"
'Cyphomandra betacea' and its kin in the genus Solanum.

http://newcrop.hort.purdue.edu/newcr...ee_tomato.html
http://www.crfg.org/pubs/ff/tamarillo.html
[links illustrating "tree tomatoes"]

I believe the Tomato is Solanum and not Lycopersicon.

Or, "Lycopersicon" is a name that was applied to one particular
small subgroup of _Solanum_.

I believe this because
I hypothesize that some million/s of years ago the Tomato plants of South
America, a few of them gained a mutation. And this mutation of a few tomato
plants had the tomato fruit buried in the soil so that the fruit became a tuber.

No. Tomatoes and potatoes are indeed fairly closely related to one
another within the huge genus _Solanum_, but the potato tuber is a
modified underground stem, not a fruit. Cultivated potatoes still
do flower and fruit [but many varieties set few fruit], and the
fruits do still look like small greenish tomatoes. Tomatoes and the
potato fruits develop from the ripened ovaries of the flowers, but
the potato tubers develop from whole branch shoots. It's a stem,
not a fruit.

http://waynesword.palomar.edu/vege1.htm

http://www.plantkingdom.com/kingdom/...ae/solanum.htm
http://www.plantkingdom.com/kingdom/...e/lycprscn.htm
http://newcrop.hort.purdue.edu/newcr...99/v4-379.html

And thus was born the first creation of the potato plant.

And since Potato plant is a Solanum, then obviously the tomato is a Solanum.

And so is the eggplant and a great many other plant species
including herbs, shrubs, woody vines and even some moderate-sized
trees. Some _Solanum_ species are common weeds, and a few are
cultivated ornamentals. Most are tropical.

http://pi.cdfa.ca.gov/weedinfo/SOLANUMC2.html
http://pi.cdfa.ca.gov/weedinfo/SOLANUMB2.htm
list some weeds

Question: do the Paleontologists have any fossil record of the tomato and
potato?

Don't know. The following site indicated "no records found"
for a search on "Solanum"

http://ibs.uel.ac.uk/ibs/palaeo/pfr2/pfr.htm

If there is any fossil record for members of this group, it may well
just be of fossil pollen grains, which would tell you very little
about tubers.

Does the tomato exist further back in time than the potato? My guess is yes
considering the above Hypothesis.

And one should be able to duplicate the experiment that Nature already did. One
should be able to find a *wild tomato* and by testing thousands of these wild
tomatoes one should be able to find one of these wild-tomatoes place its fruit
into the ground and become a *tuber*.

There are several wild species of tomatoes and also various wild
species of potatoes. Several of the wild potatoes do form tubers. The
tubers again are modified stems, not fruits. The many wild potato
species also flower and form small tomato-like berries on their
above-ground branches.

http://www.grida.no/cgiar/awpack/diversit.htm
http://ethesis.helsinki.fi/julkaisut...roduction.html
http://plants.gardenbed.com/65/6421_edi.asp
http://www.zum.de/stueber/ross/potato/herbarium_Ia.html
http://www.zum.de/stueber/ross/potato/herbarium_Ib.html
http://www.zum.de/stueber/ross/potato/herbarium_II.html
http://www.zum.de/stueber/ross/potat...arium_III.html
http://www.zum.de/stueber/ross/potato/supplement_A.html
[lists of wild potato collections]

other misc. links.
http://www.ecpgr.cgiar.org/Workgroup...solanaceae.htm
http://newcrop.hort.purdue.edu/newcr...99/v4-379.html
http://www.keil.ukans.edu/delta/angio/www/solanace.htm
http://www.ume.maine.edu/PAA/abstramgen2001.htm
http://www.ars-grin.gov/ars/MidWest/NR6/ar99.html

cheers

Thanks for that well-informed response.

Question: how far away are we from getting a entire genome project on
the *wild potato* and *wild tomato* plus all the other Solanum species?
Are we 50 years away from getting that data?

My hypothesis is that once the data is available that the wild potato and wild
tomato genomes are the closest-matching genomes of all the Solanum species.

We do have genetic data on all the primates and the Human genetics closest-
match is the chimpanzee.

So my theory is that as close as Human genetics matches chimpanzees of all the
primates, that the wild-potato matches the closest with the wild-tomato of all of
the Solanum species.

Archimedes Plutonium,
whole entire Universe is just one big atom where dots
of the electron-dot-cloud are galaxies

sci.bio.paleontology dropped.

In article , wrote...
24 Oct 2002 03:35:16 GMT mel turner wrote:
In article , wrote...
[previous snipped]

Thanks for that well-informed response.

No problem, it's a fun group of plants to look up info on.

Question: how far away are we from getting a entire genome project on
the *wild potato* and *wild tomato* plus all the other Solanum species?
Are we 50 years away from getting that data?

All Solanums? It unlikely we're that close. It seems there are lots
[over a hundred?] of different wild potato species [Solanum
subgenus Potatoe section Petota], and IIRC well over a thousand
different species in the rest of the genus.

However, there is ongoing genetic research looking into improving
the cultivated potato, including using crosses with different wild
potato species, and no doubt the potato and its closest wild
relatives would be a very likely candidate for a major genome
project of somewhat narrower scope.

My hypothesis is that once the data is available that the wild potato and wild
tomato genomes are the closest-matching genomes of all the Solanum species.

You're probably right, with the clarification that it's the whole
group of several tomato species [both wild and cultivated] that
together are the closest relative of the large group of many
potato species [wild and cultivated].

We do have genetic data on all the primates and the Human genetics closest-
match is the chimpanzee.

So my theory is that as close as Human genetics matches chimpanzees of all the
primates, that the wild-potato matches the closest with the wild-tomato of all
of
the Solanum species.

And yes, that seems to be the case [again with the clarification
that there are several species of wild tomatoes and many species
of wild potatoes. Together the two groups reportedly make
up the subgenus Potatoe of the genus Solanum, which also
contains many other much more distant subgroups.

Some references and abstracts [from a BioAbstracts search]
illustrating recent research that you may find of interest:

TI: Molecular evolution of 5S rDNA of Solanum species (sect. Petota):
Application for molecular phylogeny and breeding.
AU: Volkov-R-A; Zanke-C; Panchuk-I-I; Hemleben-V {a}
SO: Theoretical-and-Applied-Genetics. [print] December, 2001; 103
(8): 1273-1282..
AB: Nucleotide sequences of 5S rRNA genes (5S rDNA) of 26 wild
species of the genus Solanum (sect. Petota) originating from Middle
or South America, four Solanum tuberosum breeding lines and one
European species, Solanum dulcamara (sect. Dulcamara) were compared
with each other and with the 5S rDNA of Lycopersicon esculentum. The
length of the repeat ranges from 285 bp to 349 bp. The complete 5S
repeat unit consists of the 120-bp long conserved coding region and
of a intergenic spacer with a high variability in the central portion
as result of deletions/duplications of short motifs demonstrating
sequence similarity to box C in the 5S rRNA coding region. Numerous
structural rearrangements found in the spacer region can be applied
to design species-specific molecular markers for Solanum species
involved in breeding programs. Characteristic insertions/deletions
(indels) were used to reconstruct phylogenetic relationships among
the species studied. S. dulcamara forms a separate clade; L.
esculentum is more related to Solanum species of sect. Petota.
Conservation of ancestral 5S spacer organization was demonstrated
for the representatives of several series of sect. Petota, both
Stellata and Rotata. Further rearrangements of the spacer
organization occurred in at least four independent lineages:
(1) L. esculentum, (2) ser. Polyadenia, (3) other Stellata species
from Middle America (ser. Pinnatisecta and Bulbocastana),
(4) superser. Rotata. In this last group, series Megistacroloba and
Conocibaccata show a common origin, and separation from ser.
Tuberosa. Solanum chacoense and Solanum maglia demonstrate a close
relatedness to species of ser. Tuberosa and should be included
into this group, whereas Solanum bukasovii should be excluded due
to conservation of ancestral spacer organization. Three major
subgroups may be distinguished for species from ser. Tuberosa,
although a high sequence similarity was found here. Several wild
species (diploids Solanum phureja and Solanum spegazzinii) probably
participated in the natural origin of tetraploid S. tuberosum;
others were later used for crossing in breeding programs (e.g.
Solanum demissum). Clear separation of Middle-American Stellata
species from South-American Stellata and from Middle-American Rotata
polyploids is shown.

TI: Molecular systematics of Solanum section Lycopersicum
(Lycopersicon) using the nuclear ITS rDNA region.
AU: Marshall-J-A; Knapp-S; Davey-M-R {a}; Power-J-B; Cocking-E-C;
Bennett-M-D; Cox-A-V
SO: Theoretical-and-Applied-Genetics. [print] December, 2001; 103
(8): 1216-1222..
AB: The phylogenetic relationships of all nine known tomato species
of Solanum section Lycopersicum, together with other Solanum sections
and species from several related genera, were investigated using
parsimony analysis of the internal transcribed spacer (ITS) region of
nuclear ribosomal DNA (rDNA). Most parsimonious reconstructions
divided the section Lycopersicum into three clades, reflecting their
mating behaviour and fruit colour. Data from sequencing studies were
congruent with those from morphological and other molecular
investigations, and provided detailed information concerning species
relationships.

TI: Use of microsatellites to evaluate genetic diversity and species
relationships in the genus Lycopersicon.
AU: Alvarez-A-E; van-de-Wiel-C-C-M {a}; Smulders-M-J-M; Vosman-B
SO: Theoretical-and-Applied-Genetics. [print] December, 2001; 103 (8):
1283-1292..
AB: In order to determine how informative a set of microsatellites
from tomato is across the genus Lycopersicon, 17 microsatellite loci,
derived from regions in and around genes, were tested on 31 accessions
comprising the nine species of the genus. The microsatellite
polymorphisms were used to estimate the distribution of diversity
throughout the genus and to evaluate the efficacy of microsatellites
for establishing species relationships in comparison with existing
phylogeny reconstructions. Gene diversity and genetic distances were
calculated. A high level of polymorphism was found, as well as a large
number of alleles unique for species. The level of polymorphism
detected with the microsatellite loci within and among species was
highly correlated with the respective mating systems, cross-pollinating
species having a significantly higher gene diversity compared to
self-pollinating species. In general, microsatellite-based trees were
consistent with a published RFLP-based dendrogram as well as with a
published classification based on morphology and the mating system. A
tree constructed with low-polymorphic loci (gene diversity 0.245)
was shown to represent a more-reliable topology than a tree constructed
with more-highly polymorphic loci.

TI: Granule-bound starch synthase (GBSSI) gene phylogeny of wild
tomatoes (Solanum L. section Lycopersicon (Mill.) Wettst. subsection
Lycopersicon).
AU: Peralta-Iris-E; Spooner-David-M {a}
SO: American-Journal-of-Botany. [print] October, 2001; 88 (10):
1888-1902..
AB: Eight wild tomato species are native to western South America and
one to the Galapagos Islands. Different classifications of tomatoes
have been based on morphological or biological criteria. Our primary
goal was to examine the phylogenetic relationships of all nine wild
tomato species and closely related outgroups, with a concentration on
the most widespread and variable tomato species Solanum peruvianum,
using DNA sequences of the structural gene granule-bound starch
synthase (GBSSI, or waxy). Results show some concordance with previous
morphology-based classifications and new relationships. The ingroup
comprised a basal polytomy composed of the self-incompatible
green-fruited species S. chilense and the central to southern Peruvian
populations of S. peruvianum, S. habrochaites, and S. pennellii. A
derived clade contains the northern Peruvian populations of S.
peruvianum (also self-incompatible, green-fruited), S. chmielewskii,
and S. neorickii (self-compatible, green-fruited), and the
self-compatible and red- to orange- to yellow-fruited species S.
cheesmaniae, S. lycopersicum, and S. pimpinellifolium. Outgroup
relationships are largely concordant with prior chloroplast DNA
restriction site phylogenies, support S. juglandifolium and S.
ochranthum as the closest outgroup to tomatoes with S. lycopersicoides
and S. sitiens as basal to these, and support allogamy,
self-incompatibility, and green fruits as primitive in the tomato
clade.

TI: Classification of wild tomatoes: A review.
AU: Peralta-Iris-Edith {a}; Spooner-David-M {a}
SO: Kurtziana-. [print] 2000; 28 (1): 45-54..
AB: Wild tomatoes are native to western South America. The generic
status of wild tomatoes within the Solanaceae has been controversial
since the eighteen century. Linnaeus in 1753 placed tomatoes in
Solanum while Miller, a contemporary of Linnaeus, classified tomatoes
in a new genus Lycopersicon. The majority of later botanists have
followed Miller. Differing numbers of species and conflicting
supraspecific classifications have been proposed, based on morphology
or crossing studies. Two major crossability groups have been
identified, one that includes mainly self-compatible species that
easily cross with the cultivated tomato, and another that comprises
self-incompatible species not easily cross with the cultivated tomato.
Recent molecular investigations using appropriate outgroups have shown
that tomatoes and potatoes are close related phylogenetically, and
support the inclusion of tomatoes within Solanum, the classification
advocated here. We discuss the conflicting goals of classifications
based on predictivity versus stability, a continuing controversy in
systematics.

TI: Phylogenetic relationships of wild potatoes, Solanum series
Conicibaccata (Sect. Petota).
AU: Castillo-Raul-O; Spooner-David-M {a}
SO: Systematic-Botany. 1997; 22 (1) 45-83..
AB: Solanum sect. Petota series Conicibaccata is a group of 40 wild
potato species, composed of diploids, tetraploids, and hexaploids,
distributed from central Mexico to central Bolivia. This study
examined their species boundaries and interrelationships by phenetic
analyses of morphological data and cladistic analyses of chloroplast
DNA restriction site data. Mitotic chromosome counts were obtained for
114 accessions; species whose first counts are reported here are S.
garcia-barrigae, S. orocense, and S. sucubunense. Most results were
concordant in showing three main groups of species: 1) tetraploids
and hexaploids from centra Mexico to southern Ecuador; 2) diploids
from northern Peru to Bolivia, included in a cpDNA clade of diploids
and hexaploids assigned to ser. Demissa and ser. Tuberosa, and 3)
diploids and tetraploids from southern Colombia to Peru, cladistically
related to members of ser. Piurana. Some species boundaries, and even
series boundaries of ser. Conicibaccata and ser. Piurana, are supported
morphologically only by a combination of widely overlapping character
states, none of which is constant for a species. Other species have
no support, and it is likely that too many species are recognized in
the group. The cladistic analysis of chloroplast DNA data suggested
that some species represent a combination of apospecies and
plesiospecies, and some populations are of possible hybrid origin.

TI: Implications for the phylogeny, classification, and biogeography
of Solanum from cpDNA restriction site variation.
AU: Olmstead-Richard-G {a}; Palmer-Jeffrey-D
SO: Systematic-Botany. 1997; 22 (1) 19-29..
AB: A phylogenetic analysis of Solanum based on chloroplast DNA
restriction site variation confirms previous findings that
Lycopersicon and Cyphomandra are derived from within Solanum. Three
out of four Solanum subgenera with more than one representative in
this analysis (Minon, Potatoe, Solanum) are found to be polyphyletic,
suggesting that the subgeneric classification of the genus needs
revision. Subgenus Leptostemonum is monophyletic within the context
of our sampling. Three primary clades can be distinguished within
Solanum. Clade I includes representatives of sections Archaesolanum,
Dulcamara, Holophylla, Jasminosolanum, and Solanum. Clade II includes
members of subgenus Potatoe (sections Basarthrum, Lycopersicon, and
Petota). Clade III includes all representatives sampled from subg.
Leptostemonum, sects. Allophyllum, Brevantherum, Geminata,
Pseudocapsocum, and Cyphomandropsis, and species formerly assigned to
Cyphomandra. Solanum as a whole and each of the three primary
clades appear to be New World in origin. Within Leptostemonum, African
and Australian members are derived from New World ancestors.

TI: Phylogenetic relationships in Solanum (Solanaceae) based on ndhF
sequences.
AU: Bohs-Lynn {a}; Olmstead-Richard-G
SO: Systematic-Botany. 1997; 22 (1) 5-17..
AB: A phylogenetic analysis was conducted using sequence data from
the chloroplast gene ndhF. Sequences were obtained from 25 species of
Solanaceae, including 18 species of Solanum representing five of the
seven conventionally recognized subgenera. Trees were constructed
using parsimony and maximum likelihood methods. Results indicate that
Solanum lycopersicum (formerly in genus Lycopersicon) and Solanum
betaceum (formerly in genus Cyphomandra) are nested within the Solanum
clade. Each of the Solanum subgenera Leptostemonum, Minon, Potatoe,
and Solanum are not monophyletic as currently circumscribed. Four
major clades within Solanum are supported by high bootstrap values,
but the relationships among them are largely unresolved. The
problematical sections Aculeigerum (represented by S. wendlandii) and
Allophyllum (represented by S. allophyllum) emerge as sister taxa in
a larger clade composed of S. betaceum, S. luteoalbum, and members of
subgenera Leptostemonum, Minon, and Solanum. Several prominent
morphological characters such as spines, stellate hairs, and tapered
anthers apparently have evolved more than once in Solanum.

TI: Insect resistance in potatoes: Sources, evolutionary relationships,
morphological and chemical defenses, and ecogeographical associations.
AU: Flanders-Kathy-L; Hawkes-John-G; Radcliffe-Edward-B {a};
Lauer-Florian-I
SO: Euphytica-. 1992; 61 (2) 83-111..
AB: The past 25 years, 1986 potato accessions, representing 100
species in the genus Solanum L., subgenus Potatoe, section Petota,
were evaluated for field resistance to one or more of the following
insect pests: green peach aphid, Myzus persicae (Sulzer); potato
aphid, Macrosiphum euphorbiae (Thomas); Colorado potato beetle,
Leptinotarsa decemlineata (Say); potato flea beetle, Epitrix
cucumeris (Harris); and potato leafhopper, Empoasca fabae (Harris).
Accession highly resistant to green peach aphid were identified
within 36 species, to potato aphid within 24 species, to Colorado
potato beetle within 10 species, to potato flea beetle within 25
species, and to potato leafhopper within 39 species. Resistance
levels were characteristic within Solanum species. Insect resistance
appears to be a primitive trait in wild potatoes. Susceptibility was
most common in the primitive and cultivated Tuberosa. Insect
resistance was also characteristic of the most advanced species.
The glycoalkaloid tomatine was associated with field resistance to
Colorado potato beetle and potato leafhopper. Other glycoalkaloids
were not associated with field resistance at the species level. Dense
hairs were associated with resistance to green peach aphid, potato
flea beetle, and potato leafhopper. Glandular trichomes were
associated with field resistance to Colorado potato beetle, potato
flea beetle, and potato leafhopper. Significant correlation between
insect score and altitude of original collection were observed in six
of thirteen species. Species from hot and arid areas were associated
with resistance to Colorado potato beetle, potato flea beetle, and
potato leafhopper. Species from cool or moist areas tended to be
resistant to potato aphid.

cheers

In article ,
mel turner wrote:

Mel, you are posting a lot of really neat refs. Thanks! I'll have
to try to find some of these papers when I get time.

Whoever named the section Petota and the subgenus Potatoe must have
been snickering as he typed!

I found the abstract below particularly interesting in that I always
thought the eggplant (S.melongena) originated in India. I guess
Solanums are the veggies of Gondwanaland. This would make it a
really old genus, antedating the south Atlantic Ocean. No wonder
it's so huge.

TI: Implications for the phylogeny, classification, and biogeography
of Solanum from cpDNA restriction site variation.
AU: Olmstead-Richard-G {a}; Palmer-Jeffrey-D
SO: Systematic-Botany. 1997; 22 (1) 19-29..
AB: A phylogenetic analysis of Solanum based on chloroplast DNA
restriction site variation confirms previous findings that
Lycopersicon and Cyphomandra are derived from within Solanum. Three
out of four Solanum subgenera with more than one representative in
this analysis (Minon, Potatoe, Solanum) are found to be polyphyletic,
suggesting that the subgeneric classification of the genus needs
revision. Subgenus Leptostemonum is monophyletic within the context
of our sampling. Three primary clades can be distinguished within
Solanum. Clade I includes representatives of sections Archaesolanum,
Dulcamara, Holophylla, Jasminosolanum, and Solanum. Clade II includes
members of subgenus Potatoe (sections Basarthrum, Lycopersicon, and
Petota). Clade III includes all representatives sampled from subg.
Leptostemonum, sects. Allophyllum, Brevantherum, Geminata,
Pseudocapsocum, and Cyphomandropsis, and species formerly assigned to
Cyphomandra. Solanum as a whole and each of the three primary
clades appear to be New World in origin. Within Leptostemonum, African
and Australian members are derived from New World ancestors.

In article , wrote...
In article ,
mel turner wrote:

Mel, you are posting a lot of really neat refs. Thanks! I'll have
to try to find some of these papers when I get time.

Me too.

Whoever named the section Petota and the subgenus Potatoe must have
been snickering as he typed!

So, maybe Dan Quayle was correctly spelling the subgenus name?
Who knew he was so well-informed on matters concerning vegetables...?

I found the abstract below particularly interesting in that I always
thought the eggplant (S.melongena) originated in India.

I'd vaguely thought it might be from North Africa, but

http://waynesword.palomar.edu/ecoph21.htm and
http://www.museums.org.za/bio/plants..._melongena.htm
http://edis.ifas.ufl.edu/BODY_CV124
http://www.mobot.org/education/05act...egetables.html
etc.

do all say "Asia", so you seem to be right..

Anyway, I think that's not really a contradiction-- they
just seem to be saying that the whole group of African or
Asian species that eventually gave rise to the cultivated
eggplant [in Africa or Asia] would ultimately have been
derived from tropical American ancestors at some point in
the remote past. [I haven't checked their reasoning, but
it probably follows from their identifying the early branches
of the major clades as all being strictly South American.]

I guess
Solanums are the veggies of Gondwanaland. This would make it a
really old genus, antedating the south Atlantic Ocean. No wonder
it's so huge.

That conclusion seems unnecessary. The group could have
arisen much more recently, and dispersed and radiated
from wherever its place of origin happened to be. In fact,
they seem to argue for just this, since they speak of
New World ancestors, and not Gondawanaland ancestry.

TI: Implications for the phylogeny, classification, and biogeography
of Solanum from cpDNA restriction site variation.
AU: Olmstead-Richard-G {a}; Palmer-Jeffrey-D
SO: Systematic-Botany. 1997; 22 (1) 19-29..
AB: A phylogenetic analysis of Solanum based on chloroplast DNA
restriction site variation confirms previous findings that
Lycopersicon and Cyphomandra are derived from within Solanum. Three
out of four Solanum subgenera with more than one representative in
this analysis (Minon, Potatoe, Solanum) are found to be polyphyletic,
suggesting that the subgeneric classification of the genus needs
revision. Subgenus Leptostemonum is monophyletic within the context
of our sampling. Three primary clades can be distinguished within
Solanum. Clade I includes representatives of sections Archaesolanum,
Dulcamara, Holophylla, Jasminosolanum, and Solanum. Clade II includes
members of subgenus Potatoe (sections Basarthrum, Lycopersicon, and
Petota). Clade III includes all representatives sampled from subg.
Leptostemonum, sects. Allophyllum, Brevantherum, Geminata,
Pseudocapsocum, and Cyphomandropsis, and species formerly assigned to
Cyphomandra. Solanum as a whole and each of the three primary
clades appear to be New World in origin. Within Leptostemonum, African
and Australian members are derived from New World ancestors.

cheers

In article ,
mel turner wrote:
In article , wrote...
In article ,
mel turner wrote:

I guess
Solanums are the veggies of Gondwanaland. This would make it a
really old genus, antedating the south Atlantic Ocean. No wonder
it's so huge.

That conclusion seems unnecessary. The group could have
arisen much more recently, and dispersed and radiated
from wherever its place of origin happened to be. In fact,
they seem to argue for just this, since they speak of
New World ancestors, and not Gondawanaland ancestry.

TI: Implications for the phylogeny, classification, and biogeography
of Solanum from cpDNA restriction site variation.
AU: Olmstead-Richard-G {a}; Palmer-Jeffrey-D
SO: Systematic-Botany. 1997; 22 (1) 19-29..

Solanum as a whole and each of the three primary
clades appear to be New World in origin. Within Leptostemonum, African
and Australian members are derived from New World ancestors.

I read the New World ancestry assertion to be consistent with Solanum
having arisen in the part of Gondwanaland that became South America,
but it's hard to conclude anything from an abstract. I wonder if they
address this in the paper. It's hard to imagine how Solanums could
have crossed both the Atlantic and Pacific from South America, but I
don't know much about long-distance dispersal mechanisms.

Unfortunately, the university library has access to volumes 25(2000) to
present through one provider, and volumes 1-21 (1976-1996) through another
("moving wall system"). So I'll either have to wait a few months, or go
over to a physical library and find a physical journal...

Hmm, just wasted too much time searching what lit I can get at from my
desk, and it turns out that eggplants are in Leptostemonum, and can float
in seawater for five weeks and still have good seeds. This is in the
context of Madagascar which has two dozen endemic Solanum spp, but was
separated from Africa and the rest of Gondwanaland before the development
of flowering plants. Of course the straits are not all that wide.
Africa is just lousy with Solanum spp and there's a secondary center of
diversity in New Guinea. I better get back to the work I'm being paid
for...

Also consider that many species of Solanum have fruit that are berries eaten
by birds and may be carried long distances. Also the seeds are often
imbedded in a mucilaginous pulp that can stick to the beaks and feet of
birds.


Beverly Erlebacher wrote in message
. ..
In article ,
mel turner wrote:
In article ,
wrote...
In article ,
mel turner wrote:

I guess
Solanums are the veggies of Gondwanaland. This would make it a
really old genus, antedating the south Atlantic Ocean. No wonder
it's so huge.

That conclusion seems unnecessary. The group could have
arisen much more recently, and dispersed and radiated
from wherever its place of origin happened to be. In fact,
they seem to argue for just this, since they speak of
New World ancestors, and not Gondawanaland ancestry.

TI: Implications for the phylogeny, classification, and biogeography
of Solanum from cpDNA restriction site variation.
AU: Olmstead-Richard-G {a}; Palmer-Jeffrey-D
SO: Systematic-Botany. 1997; 22 (1) 19-29..

Solanum as a whole and each of the three primary
clades appear to be New World in origin. Within Leptostemonum, African
and Australian members are derived from New World ancestors.

I read the New World ancestry assertion to be consistent with Solanum
having arisen in the part of Gondwanaland that became South America,
but it's hard to conclude anything from an abstract. I wonder if they
address this in the paper. It's hard to imagine how Solanums could
have crossed both the Atlantic and Pacific from South America, but I
don't know much about long-distance dispersal mechanisms.

Unfortunately, the university library has access to volumes 25(2000) to
present through one provider, and volumes 1-21 (1976-1996) through another
("moving wall system"). So I'll either have to wait a few months, or go
over to a physical library and find a physical journal...

Hmm, just wasted too much time searching what lit I can get at from my
desk, and it turns out that eggplants are in Leptostemonum, and can float
in seawater for five weeks and still have good seeds. This is in the
context of Madagascar which has two dozen endemic Solanum spp, but was
separated from Africa and the rest of Gondwanaland before the development
of flowering plants. Of course the straits are not all that wide.
Africa is just lousy with Solanum spp and there's a secondary center of
diversity in New Guinea. I better get back to the work I'm being paid
for...

In article m,
Cereoid+10 wrote:
Also consider that many species of Solanum have fruit that are berries eaten
by birds and may be carried long distances. Also the seeds are often
imbedded in a mucilaginous pulp that can stick to the beaks and feet of
birds.

And then the bird flies from South America to Australia...

I like the floating eggplant theory better, myself, if I can't have the
'veggies of Gondwanaland' one. Btw, IIRC most birds in Madagascar are
endemics, as was almost everything in Madagascar until recently.

The flyway is between Australia and tropical Asia by way of Malaysia, do I
believe.

Most Solanum species have a mucilaginous pulp rather than a spongy one.

The present connection between Madagascar and continental Africa is by way
of the Comoros and other small island chains between them. There are a
number of fleshy fruited species that have been island hopping by that route
presumably by birds.


Beverly Erlebacher wrote in message
. ..
In article m,
Cereoid+10 wrote:
Also consider that many species of Solanum have fruit that are berries
eaten
by birds and may be carried long distances. Also the seeds are often
imbedded in a mucilaginous pulp that can stick to the beaks and feet of
birds.

And then the bird flies from South America to Australia...

I like the floating eggplant theory better, myself, if I can't have the
'veggies of Gondwanaland' one. Btw, IIRC most birds in Madagascar are
endemics, as was almost everything in Madagascar until recently.