30 Oct 2002 11:56:35 GMT mel turner wrote:


Well, in a sense you're probably more or less right,
with some rephrasing:

The last common ancestor of all modern tomatoes and modern
potatoes would actually be neither a tomato or a potato, but
yes, it would undoubtedly be more like the tomatoes in lacking
tubers. The tubers of the modern potato species are a new
feature that will have evolved in that lineage some time
after its separation from the line leading to modern tomatoes.

And yes, potato tubers [like similar organs in many other plants]
undoubtedly do often serve as storage depots for starch and
water, etc., that can help the plant survive a dormant
period or a prolonged season of unsuitable growing conditions.
So, you may well be basically right about the possible ecological/
natural selective basis for the origin of tubers in the potato
line.

[The "hot moist jungle" vs "cold dry mountains" bit may be a tad
inaccurate, but nevermind...]

cheers

Mel, two questions. Both related. Question A: has the full genome of
wild tomato and wild potato been established? If not how much longer
must we wait? And if established can we pick apart the ACTG letter code
that gives rise to a extended tomato root that is the potato tuber?

Question B: broader than question A. How good are we at present in being
able to say that a *section of the entire ACTG genome of a species* is a
particular organ? If not, then are the letter codes all contributing of an organ
and that organs cannot be sectionalized?

As to whether organs can or cannot be sectionalized with ACTG coding, my
guess would be a yes, because highly specialized organs such as the eyeball
would seem to me to need a high degree of sectionalization of the ACTG
letter coding. Perhaps sectionalization is never 100% for organs but rather
can come close to it in the 90s percent range.

Any comments or thoughts?

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