Evolution of geophytes?

Jane McGary janemcgary@earthlink.net
Thu, 07 Feb 2019 11:09:55 PST
The ways in which bulbs multiply often seem to be adaptations to 
environmental conditions. For instance, the production of numerous tiny, 
loosely attached offsets (such as "rice grains" in some Fritillaria) is 
often associated with predation by digging animals such as bears and 
humans (e.g., consumers of Fritillaria camtschatcensis, Brodiaea 
californica, Camassia). The interesting bulb of Lilium pardalinum, which 
is elongated with very numerous scales, may reflect its typical habitat 
near mountain streams, where the bulb might be dislodged and distributed 
in spring. In both cases, the forms that bore many viable bulblets or 
scales would tend over time to dominate the population.

Mark mentions Crocus and its subterranean ovary. You can tell when 
crocuses are ready to have their seed harvested because the capsule 
rather suddenly rises above soil level on a stem, so that the seeds will 
scatter. In nature one usually sees crocuses growing as scattered 
individuals, not the tight clonal clusters found in cultivation -- 
perhaps a respnse to burrowing predators.

Jane McGary, Portland, Oregon, USAOn 2/7/2019 10:30 AM, mark akimoff wrote:

> On Feb 7, 2019, at 9:28 AM, mark akimoff <makimoff76@gmail.com> wrote:
>> Hello,
>>
>> I'm wanting to put together an introductory power point on the evolution of
>> geophytes to be used in STEM (Science Technology Engineering and Math)
>> outreach at local schools. I'm interested in the story telling aspect of
>> it, and Martyn Rix' "Growing Bulbs" has a great introductory chapter on the
>> evolution of flowers that covers things like the Crocus, and subterranean
>> ovaries as an adaptation to grazing pressure. Or for instance, fall
>> blooming speciation as an adaptation to  seasonal migration of grazing
>> herds across elevational gradients.
>>
>> Beyond that book does anyone have any other books, articles, ideas,
>> theories, etc? That might be useful in introducing evolution of geophytes
>> as a curriculum? I'm leaning towards tying it in to current issues like
>> zeric adaptations for changing climate or pollution tolerance, that sort of
>> thing.
>>
>> Any help from this brain trust would be much appreciated!
>>
>> Thanks,
>> Mark Akimoff
>> illahe
>> Salem, Oregon
>> _______________________________________________
>> pbs mailing list
>> pbs@lists.pacificbulbsociety.net
>> http://lists.pacificbulbsociety.net/cgi-bin/…
>> _______________________________________________
>> pbs mailing list
>> pbs@lists.pacificbulbsociety.net
>> http://lists.pacificbulbsociety.net/cgi-bin/…
>>
> _______________________________________________
> pbs mailing list
> pbs@lists.pacificbulbsociety.net
> http://lists.pacificbulbsociety.net/cgi-bin/…
_______________________________________________
pbs mailing list
pbs@lists.pacificbulbsociety.net
http://lists.pacificbulbsociety.net/cgi-bin/…


More information about the pbs mailing list