: In article <4470@uswnvg.uswnvg.com> djwilli@uswnvg.com (Dan Williams) writes:
: >:
: >Shells also provide protection from gravity, and also from loss of precious
: >water. Large variable tides would subject a variety of sealife to the rigours
: >of a duo-environment.
:
: In the real world, the race between the tortoise and the hare was won
: by the hare. A shell limits movement and the rejection of waste heat
: to the environment. Thus shelled creatures are less active foragers.
: In the arms race between armor and speed, armor seems to have lost
: most frequently. The large armored creatures are no more while the
: agile endoskeletal creatures seem to have prospered. The design of the
: largest armored amphibian, the turtle, seems to have been frozen early.
: It has changed little in millions of years. I think rapid evolution is
: necessary for intelligence to develop, and that a hard shell tends to
: freeze evolution before it can advance enough.
:
My idea is more that evolution drives creatures for speed mainly and in a
different enviroment an amphibious squid on a sled could be a viable
alternative and provide the basis for an intelligent non-upright tool user
without an internal skeleton.
: >I would argue that Nature has worked with several successful bus designs in
: >creating different species. Insects do walk on a double tripod base,
: >I know of no three legged species but 5 limbs are common amoung some
: >groups, {Elephants, and new world monkeys} How about snakes? Crustaceans,
: >clams, or slug. The squid might be a good base design. Grow a shell to provide support, use large tentacles to pull the body along and retain the smaller
: >tentacles as manipulators combined with the mandibles to provide leverage.
: >Of course this creature requires either wheels under the shell, or a natural
: >environment of a thick algal mat to ease the drag on its shell. :-)
:
: I was suggesting that bipedal locomotion requires a more complex brain
: than more stable bases. Whether one forces development of the other is
: subject to debate. I suspect a feedback occurs. If we want to end up with
: intelligence, we should prefer forms that encourage development of complex
: brains. Neither 2 nor 4 limbs offer unconditional stability in motion
: while the double tripod of the insect does.
:
Good point, but most birds are bipedal and don't seem to require more
intelligence than your average dinosaur. Elephants are fairly intelligent
4 leggers but they have that 5th manipulator attached. So maybe a multi-
leged creature grown large enough with specialization in some limbs would
drive a species for intelligence.
: >I would consider it to be a falacy to expect life to have evolved under rules
: >simular to what guided life on this planet. Materials taken advantage of
: >could be diferent, as could base structures. What if the intelligent creature
: >is some form of communal organism.
:
: I suspect carbon chemistry forces common structures for life. I don't
: expect a creature to have titanium bones or Kevlar skin simply because
: the creation of such things isn't compatible with the energetics of carbon
: life chemistry. Life tends to fill every available niche, and the Earth
: offers a very wide variety of niches, yet most creatures follow a common
: pattern of material usage in their construction. I don't think this is
: accidental. I suspect this is the only way the chemistry allows. Silicon
: creatures breathing a fluorine atmosphere seem far fetched.
:
Creatures that excrete poisonus calcium and use it as structural material is
unusuall also. Plants have found a different route to achieving great size.
I am not suggesting wildly varied biology myself but maybe some different
material use and processing by alien life forms will allow a different focus
to their rules of evolution. I don't feel that all options have been
exhausted in the development of life on Earth. We have developed some life
forms with unusual characteristics ourselves. Microbs that eat oil, potatoes
that grow plastics, etc. And we are just rearranging what is already here.
How about using spider silk as a structural material rather than calcium?
Light, easy to work with and stronger than steel. How about a life form that
instead of secreting calcium secretes iron from it's environment?
: As to intelligent communal organisms, I suspect that inter-unit communications
: would be too slow and too limited to make that work.
:
A common characteristic in intelligent mamals is a complex social structure.
Inter unit communications may not be required for most common interactions
with the environment. Only in the later stages of the evolution of an
intelligent life form does communication really develope. Insect evolution
drives species to work as communal organisms that are suprizingly successful
without being slowed down too much by communication.
: >: Thermodynamic considerations of surface/volume relationships would
: >: seem to dictate that active complex creatures stay in a size range
: >: similar to what we see about us. 6 inch tall intelligent aliens
: >: seem unlikely, as do those much larger than the elephant.
: >:
: >Giants were not unknown in this world and given a little longer development
: >time may have produced intelligent tool users. Our own species ranges from
: >7 foot giants to under 3 feet tall. It might have been harder to survive
: >outside that range, but we really don't have enough of a sample to say it
: >is impossible to be intelligent tool users on either end of the scale.
:
: I think we can be fairly confident of the lower bounds due to the
: necessity for complex brains and the need to regulate temperature.
: The top end is less clear. I'll concede that intelligent dinosaurs
: may be a possibility. But I don't think they'd succeed in competition
: with creatures in our size range. As I said above, life seems to actively
: fill all possible niches, so it's highly likely that such competition
: would exist. The thermodynamics favors the smaller creature when high
: activity is required. I suspect that "monkey curiosity" is a prerequisite
: for intelligence of high order to develop. A large sluggish creature wouldn't
: be able to sustain that.
:
Giants were selected against by asteroids.:-) The same fate may still befall
us. Intelligence did not develope in the giants. All this tells us is that
intelligence is not a necessary biproduct of evolution, or at least it is not
allways successful. Speed on the other hand is selected for, as is
flexability in an organism. Large creatures need not be sluggish. "Monkey
curiosity" is shown by most highly intelligent creatures. They explore
their enviroment, investigate novelty, play. We don't know what came first,
its a chicken and egg type of problem. The more we learn about intelligence
the closer we find ourselves to the other animals in our world. We are not
so much unique as extreamists/specialists.
I do not belive intelligent tool use is only to be found in medium large
upright bipeds. I think we were in the right place at the right time to
develope as we did. Life is easy and common on our planet, but we are the
only species so far to have made it to the point where we could leave this
planetary environment and seek out new niches in our solar system to exploit.
If we ever do make it to another solar system with intelligent life forms I
think we should keep an open mind as to what they will look like.
The biggest suprise I could think of would be to find myself.
