Quoting Allen Aigen <[log in to unmask]>:
> Yes. the salt-water stickleback fish that were isolated in a small
> area that became fresh water and quickly evolved to meet the new
> environment is a great example of evolution at work. Were any
> marine snails caught up with them that also evolved to meet the
> challenge?
* the Sticklebacks were already anadromous, breeding in freshwater, so
they didn't need to evolve an adaptation from saltwater to fresh. I
haven't heard of any post-pleistocene colonization of freshwater in
Canada by marine snails.
For those who want to while away some New Year's time in marginally
Mollusc-related literature, our annual letter is up under the heading
of "You can find out more about our activities than it's likely anyone
would legitimately want to know..." at http://pinicola.ca/aboutus.htm
fred.
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> We have many cases of isolated populations that are distinctive,
> but we usually lack the necessary data to say whether these are new
> species (or subspecies) or just geographic variants.Some groups seem
> to evolve quickly, like the conidae, which are specialists in their
> feeding, where small changes in the toxins produced by a geographic
> subgroup can apparently quickly lead to genetic isolation and
> speciation. Other groups are generalists, like Fasciolaria and
> Busycon, where it takes long periods of isolation to effectively
> form a new (sub)species. Always more questions come up the more you
> answer.
> Allen Aigen
>
>
> From: steve rosenthal <[log in to unmask]>
> To: [log in to unmask]
> Sent: Friday, January 1, 2016 12:55 PM
> Subject: Re: [CONCH-L] Crepidula sex change
>
> the linked-to article on the Smithsonian page herein about the
> Stickleback fish in ALaska was equally interesting, and more important
> perhaps from an evolutionary perspective....actual change/speciation
> occurring in the blink of an eye, relatively speaking.
>
> On 12/31/15, Allen Aigen
> <[log in to unmask]> wrote:
>> Ain't love wonderful?
>> The power of touch: Sex-changing snails switch sooner when together
>>
>> | |
>> | | | | | | | |
>> | The power of touch: Sex-changing snails switch sooner wh...Many animals
>> change sex at some point in their lives, often after reaching a certain
>> size. Snails called slipper limpets begin life as males, and become female
>> as t... |
>> | |
>> | View on www.sciencedaily.com | Preview by Yahoo |
>> | |
>> | |
>>
>> Allen Aigen
>>
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Frederick W. Schueler & Aleta Karstad
Mudpuppy Night - http://pinicola.ca/mudpup1.htm
Vulnerable Watersheds - http://vulnerablewaters.blogspot.ca/
ANNUAL LETTER NOW POSTED AT - http://pinicola.ca/aboutus.htm
RR#2 Bishops Mills, Ontario, Canada K0G 1T0
on the Smiths Falls Limestone Plain 44* 52'N 75* 42'W
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