[ExI] kepler study says 8.8e9 earthlike planets

[Kelly Anderson]

On Fri, Nov 8, 2013 at 11:33 AM, spike <spike66 at att.net> wrote:

> Why is dry land [inherently] better for smarts than ocean?
>

Evolution requires a few things that are harder to get in the ocean.

First, and perhaps most important, in order to get new species, you have to
have geographical separation of two cousins for a period of time so they
forget how to interbreed. That is harder to come by in the ocean than on
land where you have mountains, rivers, etc. dividing things up. There are
fewer niches to occupy in the ocean than on land. So evolution tends to
wash out a bit in the ocean. That is it goes slower.

There are estimated to be approximately 28,000 species of fish. 15,300
species of marine (saltwater) fish were cataloged in the Census of Marine
Life database. Another site says there are 27,500 species of freshwater
fish. But this article:
http://www.dailymail.co.uk/sciencetech/article-2097874/There-actually-ARENT-fish-sea-Rivers-lakes-contain-80-Earths-species--despite-covering-2-surface.html


states what I expected to find, that "There are more fish species in
freshwater than in saltwater habitats, despite the much greater area and
volume of the oceans"

"Despite covering 70% of the Earth's surface, marine environments contain
only 20% of all its species." By marine, I think they mean saltwater, but
I'm unsure.

So one of the numbers or facts above is suspect as they seem to be
contradictory.

However, I'm going to go with the 80% of the fish species live in fresh
water despite it being only about 2% of the water out there because rivers
and lakes provide the separation required for speciation, whereas the ocean
does not do this nearly as well.

While it is possible to evolve very good tentacles underwater, nothing like
hands has evolved underwater. Part of the problem is that water tends to
evolve creatures that are streamlined. Hands, are clearly not very
streamlined. Could tentacles lead to intelligence? Perhaps. But without
high rates of speciation, it would take much longer in the ocean than on
land.


> To be tech enabled, you definitely need to get dry somehow.  You can
> concentrate elements, do jillions of experiments that can never be done
> without dryness.  Kelly’s notion of hands I am still pondering, but I was
> thinking of how limited is the range of experiments without dry land of
> some sort, and the materials limitations.
>
>
The smartest animals that evolved entirely in the sea are the cephalopods,
octopi and their cousins. They are smart enough to open bottles and the
like.
https://en.wikipedia.org/wiki/Cephalopod_intelligence
I don't believe that they are nearly as smart as most mammals, but I can't
back that up with any particular data.

-Kelly
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.extropy.org/pipermail/extropy-chat/attachments/20131113/eb0a9e68/attachment.html>