What will ET look like when we meet him/her/it?

Posts tagged ‘Biology’

Redemption of Octopus: Betrayal of Octopus part 2

A while ago I wrote a post bemoaning the Betrayal of Octopus.  It was indeed a foul deed.  Octopus made a hole in my wonderful argument for intelligence being the result of society and language.  Recently, I listened to an interview of David Brin on the Geeks Guide to the Galaxy podcast.  He discussed many fascinating subjects but he also declared he didn’t think aquatic species such as dolphins and octopi could develop an industrialized society.  Even worse, this podcast occurred before I started trashing Octopus.  This is tragic.  Not only did my Betrayal of Octopus post not get very many hits, it wasn’t even original.  So now I must redeem Octopus in order to regain my originality and then I can find someone else to trash.

David Brin’s assertion was that aquatic species could not form industrialized societies because they lack the ability to make fire.  He is right.  Fire does not burn underwater.  There are fires that can burn when in contact with water, but fire by definition needs oxygen in order to burn.  No fire to make steel among other things means no industrialization.  Or does it?

The reason octopi don’t form cooperative societies is because in our ocean, nutrients and oxygen are widely dispersed.  For the amount of space in the ocean (lots), there is not a lot of life in most of it.  Tropical coral reefs and the phytoplankton blooms near Alaska are exceptions, rather than the norm.  Why is this?  First of all, terrestrial space and ocean space are very different.  Both the ocean and the land are hard surfaces with a fluid space above them.  For the ocean, the fluid is salt water and for the land, the fluid is gaseous compounds.  Salt water is much denser than air, so organisms can be entirely supported by the fluid.  In the terrestrial sphere, even birds must land occasionally which is not the case in the oceanic sphere.  Humans build structures off of solid surfaces and I’m going to assume a solid surface is necessary for structures.  Second of all, most animal life on earth depends on gaseous oxygen (dissolved in water or straight up).  There is a lot of space in the ocean that doesn’t have very much oxygen.  Third of all, because there’s a lot of space without oxygen, there’s a lot of space without a lot of life.  Being sans life, means there’s nothing for animals to eat.  All of these reasons mean it is more efficient for octopi and other animals to spread out, especially a reasonably smart animal that can find food even if food is hard to find.

What if the character of our ocean were different?  What if some natural process injected enough gas for organisms to breathe in the ocean almost anywhere?  What if the ocean was as full of life as the majority of terrestrial space?  What if octopi could clump together?  I think octopi would be more social and have a capacity for language similar to dolphins.

At the start of our industrial revolution, one of the many possibly catalyzing technologies was the water wheel, a version of which I am sure Octopus (if he were the social type) could build and utilize.  There may not be fire in the depths of the ocean, but maybe octopi could utilize lava flows and smokers to work metal.  Octopus is pretty smart after all.  There you go, Octopus, I forgive you for busting up my theory because I got to make a new one!

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Variability and evolution

Last post, I asked: would life in a stable environment evolve past the primordial ooze stage and what level of environmental variability is good for the evolution of intelligent life?

One of my college professors described evolution quite simply.  He wrote, “Evolution is change” and left it at that.  I’ve spent a long time trying to add qualifiers to that definition, because I, an individual, change and individuals cannot evolve.  I’ve always thought that as a model, the “evolution is change” definition is too simple to be really valuable.  Mathematically, though, that particular definition of evolution is useful.  If one defines evolution as change, finding the rate of evolution in a population becomes a calculus problem.

There are two competing theories about the rate of evolutionary change, punctuated equilibrium and gradual change.  The punctuated equilibrium theory argues that, because we see relatively few individuals in the fossil record in the process of speciation, speciation and evolutionary change happen quickly (thousands of years rather than millions).  Then species remain relatively unchanged for the remainder of their history.  The gradual change theory argues that the fossil record is not nearly complete so we should not expect to find examples of speciation, and that evolutionary change happens slowly but consistently.  I think these two theories are both present in the natural world, and the two theories can be combined.  Check out my super simplistic illustration of the concept below!

 

 

The chunks where rapid evolutionary change occurs would be caused by a big change in the organism’s environment.  Most of the time though, chunks of gradual evolutionary change would be caused by small changes in the environment and other processes on a small scale.  A stable environment could hold organisms that evolve intelligence, but I think evolution would be slow.  Instead of the 3.6 billion years it took to get us and our industrialized society, it would take what?  7 billion years?  14 billion years, the entire life of the universe?  Thankfully, our star is pretty young, so it might be possible for a species from a stable environment to evolve intelligence and then come find us as we evolved intelligence.  I don’t think it’s likely though.

What level of variability is good for intelligent life?  We can look at major sources of extinction and evolutionary change in the past to find about the stability of our environment.  Here’s a brief list of possible causes for major extinctions: Temperature shifts, atmospheric changes, shifts in our magnetic field (look at Mars!), food sources vanishing, competition.

Earth has a relatively narrow temperature band (compared to Mercury, or the prison planet in Chronicles of Riddick) from 57.8o C (136o F) to -89.2o C (-128.6o F).  Water doesn’t even get to boiling, here!  Our atmosphere has had some pretty extreme shifts in the past but it’s been pretty stable for a long time now, with a Nitrogen, Carbon Dioxide, Oxygen mix that suits us well.  The magnetic field has also been consistent for a long time, preventing solar winds from removing our ozone layer.  Our ozone layer is important in preventing radiation from frying us.  Life in general can deal with extremely variable environments but intelligent life needs a relatively stable abiotic environment in order to evolve I think.  However, I also think that the biotic environment (competing organisms, prey species, etc.) needs to be fairly complex in order for intelligent life to thrive.

Sorry, folks.  This post was not as exciting as the last one.  However, if someone knows of an equation that’s been used to express the concepts above, I would give you an honorable mention in the next post if you could bring it to my attention!

So Freakin’ Cute!

“I love frogs because they’re just so freakin’ cute.”  This Awesome Statement of Awesomeness was uttered by my boss’s 8-year-old daughter.  Then, I’m afraid I undermined my boss’s authority by cracking up.  I have to agree with her, frogs (and salamanders and snakes and lizards and iguanas all) are really, really cute.  I want to study them and have them as pets and hug them and hold them and feed them and ……. I just really think they’re awesome, ok?!

However, I don’t think they (the frogs, salamanders, snakes and lizards, hereafter referred to as herpetofauna) have what it takes to be intelligent.  One of the major differences between us and them is that we produce internal heat by metabolism, which we call endothermy.  Birds and the other mammals share this trait with us.  Herpetofauna and just about every other creature on earth do not.

Photograph is the sole property of the writer of extraterrestrialscience.wordpress.com.

Salamanders are cute! Not smart…unfortunately

Why is this important?  Our brain operates in a very narrow range of temperatures (95-100 degrees Farhenheit).  If we get too hot our brain cells do funny things like die.  Hypothermia, the other end of the spectrum, results in low oxygen in the brain, which is also bad for you.  In order to operate our brain at maximum efficiency, we need to keep it in the ideal range.  Herpetofauna on the other hand cannot produce their own heat in most cases, nor do they have effective mechanisms for dealing with too much heat.  Their means of gaining and/or losing heat are all behavioral (sitting in the shade or sun, going swimming, etc.).  As such they cannot maintain a constant temperature most of the time and their brains do not operate at maximum efficiency.

Most of the animals displaying characteristics approaching intelligence, elephants, primates, dolphins, whales and crows, are endothermic.  There is one big exception to this statement.  Octopi are the major invertebrate “smart” animal.  They are not endothermic and yet they are smart enough to outplan two graduate students.  However, they live in an environment with a relatively stable temperature.  They don’t need to produce heat to maintain a stable temperature because the unique chemical nature of water does that for them.

What does this mean for extra-terrestrials?  On a stable planet, with a (relatively) stable temperature, intelligent life forms would not need to produce their own heat, which is metabolically expensive.  Intelligent life forms from that planet could be lizard/frog-like.  Which would be so COOL!!  On a variable planet like ours, however, intelligent life would probably be more like mammals or birds.

Dark Armies of Primordial Ooze

Once upon a time, two globs of primordial ooze met and fell in like. They then decided to form a Dark Army to compete with other globs of primordial ooze! Dark Armies of primordial ooze have evolved at least twice, once in plants and once in animals. What about multicellularity is so great?

Most modern life forms have cells contained by phospholipid barriers. There is probably a maximum size limit to the amount of space that can be contained inside the phospholipid barrier. Until the evolution of multicellular organisms, that meant that the size of the organism was limited by structural components of the cell. After this evolutionary leap forward, the size of the organism was no longer limited in this fashion. Multicellular organisms would therefore be able to out-compete other organisms where size confers an evolutionary advantage.

All life would begin as single celled organisms, but on most planets, I think this advent of multicellularity would occur. Your assignment, O (hypothetical) reader, is to comment on environmental conditions where large organism size would or wouldn’t impart an evolutionary advantage. Fred Meyer has a 1 hour internet time limit, so tissue differentiation will have to wait for next time!