Space Forum / Space Science / September 2008

A good indication that said life will not be good conversationalists
though.

If it was among the denizens of the pre chlorophyll world, I doubt
anything would have survived.

Neither do birds, IIUC. Considering what some bird can do with very
small brains . .  ..

That's not logical.  The same argument "proves" that sex,
multicellularity, DNA, lipid membranes and mitochondria
are "totally useless for evolutionary success".

Not sufficient; the definition of evolutionary success is occupying and
dominating an ecological niche.  A species can reproduce and yet become
extinct if it is preyed on by another species.

Those Galapagos finches Darwin studied were successful NOT because they
reproduced; that's the mechanism, not the goal.  Their success was that
they *radiated* into all the available ecological niches on those islands.

The value of intelligence is it gives the species the ability to quickly
occupy new ecological niches without needing to evolve genetically.
Humans became the top predator on Earth without taking millions more
years to evolve bigger fangs and larger size and faster legs than
saber-toothed cats and other existing predators.  We did it by
outsmarting the saber-tooths and any other species vying for the top
predator niche.

What intelligence did for humans was NOT to produce more offspring than
beetles.  It enabled humans to become farmers (herbivores); hunters
(carnivores); SCUBA divers (deep-sea swimmers); fliers; and most
recently, outer space explorers.  We did all that without needing to
wait millions of years to evolve wings, gills, carapaces, etc.  Thus
humans colonized the entire planet, including the oceans and the air and
soon outer space.  All ecological niches.  All by the same genetic humans.

OK, I read your post carefully, and agree with you in every case
where you challenged me on a point of fact (with one or two
marginal exceptions).  Therefore, to keep this reply reasonably
clean I have snipped everything up to your concluding paragraphs
which I will write away from.  Sorry about the length.

To convince you that intelligence is an inevitable (or at least
a not improbable) consequence of evolution I believe I must
demonstrate that it has a function in a specific type of niche.
I must also show that that niche will pretty much always come
into existence during an evolutionary process and that the
function is sufficiently important that evolution will always
drive some creatures toward it.  What follows is my first
attempt:

To lay the groundwork I will first return to your assertion
that all groups should be increasing in intelligence in
response to an increasingly complex environment:

Basically, this isn't necessary, there are lots of other ways
of responding to complexity like:

- hide in the mud or dirt (worms, bivalves, many insects)
- breed so fast that you reproduce faster than you're eaten
- organize yourself so that if most of you is eaten, you keep
  growing anyway (plants)
- remain so small that it's hard to find you
- grow too big for anything to eat you
- develop a hard to penetrate shell
- become completely inedible (starfish)
- develop a better digestive system so you can eat a larger
  variety of things that are trying to be inedible
- developing a really good immune system
- become poisonous
- develop immunity to poisons, which among other things will
  often allow you to eat poisonous plants and animals
- become really fast

and so on.

Some combination of other strategies like the ones I have
mentioned above will frequently make much intelligence
unnecessary and often completely useless.  With the possible
exception of an immune system all the above appear easier to
achieve than intelligence, so most life forms are going to
"choose" one or more of the alternatives in most situations.

I hope that deals with your {everything should be getting
smarter} objection.  If so, it remains for me to show what
specific environments strongly favor the development of
intelligence.

I think that can be seen just by considering what most
intelligent animals have in common:

1 they are often wandering around in the open.
2 they eat a wide variety of foods.
3 they are themselves good to eat.
4 they are almost continuously active.

There are quite a few complicating exceptions and probably
other and better ways of organizing this list, but I am hoping
you get the idea.

The first two characteristics are both desirable and the third
is (I believe) a biproduct of needs created by the first two.
The forth I don't see as important and results (I believe) from
the need to feed the demanding brain.

The main driver is the benefit of being able to eat a wide
range of foods, or at least switch quickly when conditions
change.  (I note that Steven L mentioned this in one of his
posts too.)  Being able to switch food sources is obviously a
very good hedge against short term shortages as well as long
term extinction.

As a practical matter an animal can rarely use multiple food
sources unless it is highly mobile, and in many cases you must
be among the most mobile animals about or somebody else is
going to eat your lunch before you, or often lunch is going to
run away.

The high mobility requirement usually implies that you are good
to eat because you need things like flexible muscles to achieve
that mobility.

Thus, I contend, that there are clear practical reasons why
good-to-eat mobile creatures will arise in any ecology
containing multicellular organisms.

But obviously, if you are mobile and good eats, some of those
other mobile creatures are going to start eating you.  So you
will need to augment your senses with software filters (brains)
that allow you to reliably detect and then take the actions
needed to evade your predators.  Which will require your
predators to ... and you know better than I how an arms race
works.

OK, now I think I've got myself to the point where I have shown
that the development of intelligence is at least an expected
(and nearly inevitable) consequence of evolution following
multicellularity.

I think it is also useful to try to account for the bumpiness
(the starts and stops in the arms race leading to increasing
intelligence).  For me the cause of this bumpiness seems
obvious:

At root, brains are really expensive to maintain.  We
continuously use about 20% of our rest energy to maintain our
brains.  Obviously, no animal can afford an energy sink this
large unless it is continuously at least paying for itself, in
resource acquisition and/or predator avoidance.  Thus static
brain size (or even shrinkage if efficiencies are "discovered")
will be the norm over most evolutionary time.  This will be
reinforced by the use of metabolically cheaper solutions like
quills, improved hearing etc.

Thus, major improvements (especially those involving brain size
increases) will only occur when a species has a big problem (or
perhaps a big opportunity) that cannot be handled in another
cheaper (and findable) way.  Human evolution during the last 3
million years seems to present a pretty obvious case in point:

There we were, out on the savannas with the protective forests
dying all around us.  Slow moving lunch for large predators,
and much of what we'd like to eat could run faster than us and
so on.  The quickest fix was an increase in brain size to
facilitate more effective cooperative behaviour together with
tool making and so on.  No metabolically cheaper evolutionary
solution (apart from extinction) appears to have been
available, because humans were so much slower and poorly
defended than everything else in that environment.

Once the predators and food supplies were no longer an
overwhelming problem, we got progressively better at
exterminating each other, which helped keep the brain growth
process moving along.  (I know about the sexual selection model
but am skeptical of it.)

Although I can think of no way of proving (or even
demonstrating) it, I suspect that brain size increase didn't
quickly top out in humans, because each incremental increase
was more than compensated for in terms of the additional
resources that could be accessed to fuel the larger brain.
(The big brainers could always out-compete their smaller
cousins)

So basically, I am pitching the idea that abrupt increases in
brain size are caused by periodic environmental
changes/problems that cannot readily be solved by other means.

You have previously argued that multicellularity (another
pre-adaptation) may have been a one-off, so I'd like to briefly
address that before turning to bilateralism.

There are lots of ways of looking at this question, but all of
them boil down to competition forcing innovation.  We are
pretty sure that eukaryotes themselves arose in large part as
an adaptation to parasitism where a host worked out a
cooperative arrangement with some pre-organelle parasites, and
over a long enough period of time weird combinations like that
are going to lead to innovations which will eventually lead to
things like multicellularity and sexual replication and so
forth.

Multicellularity looks particularly likely to arise because of
bacterial mats, which although they are not single organisms,
their members do frequently cooperate together in ways that mimic
multi-cellular organisms in order to monopolize some resource
like sunlight.  Thus, there is pressure on (or an opportunity
for) some other organism to become truly multi-cellular in
order to compete more effectively with the mats.

Thus I think that something eukaryote like would have arisen
eventually and multicellularity thereafter, although I must
admit that I don't really understand what special properties
eukaryotes have that make them unique candidates for
multicellularity.

Bilateralism I see completely differently.  Just as no sea
animal can crawl out onto land to begin evolving air breathing
lungs to function on land, without being eaten by a raccoon,
and likewise no other species can evolve our level of
intelligence (unless we want it to); bilaterals also have a
huge advantage in incumbency.

To save space and effort, I won't make the argument here, but
it seems obvious to me that evolution was extremely rapid
following the introduction of bilateralism, giving rise almost
immediately to Arthropoda, Vertebrata, and Mollusca thereby
taking immediate possession of all available niches.  Thus it
happened only once because it was such a good idea.  Also since
we see a failed effort at trilateralism in the fossil record
(the name of a famous university is struggling to rise into my
consciousness), other attempts at bilateralism would surely
have occurred as variants of that.

I don't agree with this logic at all.  Secondarily, the Asian
super continent (including Africa and India) is a big place with
many competing species that can drive innovation in one
another.  In smaller locations with less complex environments
and lower variation, like islands; useful innovations (like
flight) are more likely to be lost than generated.

North and South America (which must be treated separately since
they only joined up recently) and Australia may add variation
but won't produce the most effective competitors.  Thus, I
think the Asian super continent is the place where a major new
innovation (like advanced intelligence) was most likely to occur
first.

More importantly, the preconditions for the development of
advanced intelligence have been in place for maybe 150 million
years.  So the 3 million years we took to make the move
represents 2% of that time slot.  Thus at any particular
moment, any particular candidate group (say Otters) had no more
than a 1/50 shot at the top position.  Since we wiped out lots
of other species (probably including at least two other hominan
subspecies) in our climb, it is clear that we aren't gonna let
no dolphins muscle in on our territory now that we got it.

If the Otters had beaten us to the punch, we would now be at
least as screwed as the dolphins now are.

Thus in summary:

Users of Intelligence occupy specific types of niches featuring
mobility and flexible eating habits. To effectively occupy this
type of niche an animal pretty much must have intelligence.

Creatures occupying this type of niche frequently get into arms
races with each other, which sometimes involves intelligence
itself, which will then increase unless a less costly
alternative adaptation is available.

Since these arms races are periodic increases in brain capacity
follows a bumpy path.

On the deeper issue of: is intelligence a likely outcome of any
arbitrary evolutionary process beginning from single celled
creatures:

Well obviously it cannot evolve in an environment where
complexity and thus competition are strongly constrained, as for
example, in the subsoil of Mars.

However, in any environment where multi-dimensional arms races
can get going, innovations for prerequisites like multicellularity
and bilateralism are close to inevitable.

I hope I haven't made you sick, but I can never guess with you.

Cordially;

Friar Broccoli
Robert Keith Elias, Quebec, Canada  Email: EliasRK (of) gmail * com
Best programmer's & all purpose text editor: http://www.semware.com

--------- I consider ALL arguments in support of my views ---------

Twice: psitaccoformes and hominoids. Corvoids do well too.