Monday, February 15, 2016

The limits of adaptation

Evolution has populated the earth with an utterly remarkable range of life. Even today we are don't know exactly how many forms its takes and there are constant surprises, with life been found in the most unlikely places (extremophiles)

However as a process it has three fundamental limitations. 

Firstly it is essentially reactive. Most often most creatures thrive best when their environment is stable during which time there will be little if any evolution. Major changes are most often brought about through upheaval. There are many examples of creatures that, essentially have not changed much over hundreds of millions of years. The coelacanth  is a famous example but many others have not really changed much over the millennia, e.g. sharks, crocodiles.

The second problem is that it relies on chance. External catastrophes such as such as the rogue comet hitting earth as happened for the dinosaurs mentioned above are one example. However equally important are the random mutations that happen purely by luck, the vast majority of which are deadly. Just a tiny proportion have the capacity to be beneficial and even these will be useless if they do not happen to coincide with other propitiative conditions.  

The last issue is that it is constrained by the limits imposed by reality, especially 1 and 2. For example there was a time when all vertebrae were water bound. Vast areas of dry land were filled with plentiful supplies of food and no predators, a veritable paradise. However the fish of the time could not take advantage of this. The characteristics they had evolved for life in the water prevented them, they would be starved of oxyen as their gills failed, their streamlined forms lacked the means necessary for propulsion. They were trapped in water and it would take millions of years for them to make the transition. Even then it was through the very unstatisfactory route of the amphibian, still very limited through the need to remain close to water for reproduction.

Sunday, January 31, 2016

Means to Adaptation: Co-operation, Co-opting and Coercing

Sharing a burden often makes it easier to manage and such is the case with evolution. Mostly species are in competition with each other fighting over limited resources or in the endless conflict of predator vs prey

However often the whole is greater than the sum of its parts and so, frequently, different forms of life become reliant on others for their survival and adaptation.

Perhaps the best known and most widespread example of this is pollination. Plants face a fundamental problem when it comes to evolution. Most always the adult forms are stuck in one place. So when they reproduce they can only do so in a very limited environment and with a very limited set of partners. Both prevent the spread of the species and diversity that are crucial if the species is to thrive. 

To address this many plants have come up with a beautiful solution. They use their ability to create food from sunlight to produce a concentrated type of energy in the form of sugar that is highly desired by  animals, who are incapable of producing food directly and so must find it. 

The plants advertise this "free food" by way of, often, beautiful elaborate displays that we call "flowers". Built into these are the basic cells plants use to reproduce. So when animals come to feed they also come into contact with these and spread them far and wide. 

Further, the seeds that result from this happy process are often embedded in yet more tasty food in the form of fruits. Animals which forage and eat these spread the indigestible seeds far and wide later, not only causing them to spread but also providing some healthy compost to help with their germination. 

This win-win relationship between species is called "symbosis". It has a darker twin, the parasite. There are many examples across most every form of life where one species takes advantage of another. Perhaps the most famous is the cuckoo, laying its eggs in other bird's nests and fooling them into rearing them. One of the most creepy is  Toxoplasma gondii which has a near foolproof life cycle. It infects mice and makes them less scared of cats so that they are then eaten by hungry felines (mostly feral), which can then serve as a reservoir for the parasite, since it sexually reproduces in a cat’s intestinal tract.

All in all then there working with others is an integral and crucial aspect of evolution. 

Wednesday, January 13, 2016

Means to Adaptation: Specicifity

A second means of adaptation is "specificity". To a degree this is a bit of a contradiction as it involves the fine tuning characteristics to fill out an evolutionary niche,

This is often found on islands which have specific features which can result in particular characteristics. One example is dwarfism where species shrink in size so that they become less dependent on food which is often in limited supply. The normal downside of this route is vulnerability to predators but this disappears if no such creatures have found their way across the sea. 

The downside of this route is evident when new species arrive. Sailors wrought unintentional havoc across the pacific when  rats that accompanied them on their voyages made their way into a virgin paradise. And, of course, the epitome of an evolutionary dead end is the dodo, whose lack of slight and absence of fear made it easy pickings. 

Still some element of specificity is a part of the way all creatures adapt, it's just, as is so often the case, a matter of balance.

Saturday, January 2, 2016

Means to Adaption: Rapid Reproduction

Organisms need to adapt in order to survive through generations in order to meet the various challenges that chance over time will throw at them.

There are various primary means they do this. None is exclusive, most species adopt a mix of them.

The first is Rapid Reproduction: This uses the rules of mathematics to their advantage. The wheat and chessboard fable illustrates the power of this approach. If an organism reproduces rapidly either in terms of speed and/or number of offspring it gains two major advantages. Firstly, it increases the chance of beneficial mutations each generation. Say the chance of such is 1 in a million. If the creature reproduces at the rate of two offspring a year then this will take 20 years. If it reproduces at the rate of 8 offspring per day this will take 6.5 days. In good conditions bacteria can double their population every 30 minutes. This is the why they are, in terms of sheer numbers,ubiquity and persistence amongst the most successful forms of life. 

Secondly if a species increases its numbers rapidly it can take maximum advantage during times of plenty. Its overall population will grow and, apart from providing more offspring for future directions, this allows or even forces the surplus to explore new environments causing the species to spread geographically.  

This approach is not without its disadvantages however. Bacteria can only reproduce so rapidly due to their simplicity. More complex organisms such as fish waste resource by producing millions of offspring only a tiny proportion of which will survive. Even more complex species like rodents pose a risk to themselves if their numbers overwhelm the resources available to support them. 

That said rapid reproduction is very effective in allowing species to thrive.

Tuesday, December 1, 2015

Adpatation of the Luckiest - Why does it matter? Reason 2 We need answers

The second reason Adaption of the Luckiest is important is about what it tells us about ourselves. This in turn leads to further insights into questions of why and how.

When faced with the beauty of life and other aspects of the various realities like the orbit of the sun and moon almost every culture in history has come up with reasons to explain them, most often in the form of super beings aka gods.

For this to be the case there must be something deep within the human psyche that wants understanding, we cannot just accept the realities as they are. 

Moreover the fact that much can be explained, as it has been, through the relatively simple interaction between some basic rules and luck disconcerts us. It feels inadequate, there "has to be" some deeper meaning. 

We are quite unique in this. None of the other creatures inhabiting Earth give a damn. They just accept things for what they are. Paradoxically their ignorance gives them a better grasp of the nature of realities 1-6 than those who conjure up gods and the like to explain it. 

This is,emphatically, NOT to say that these views are of no worth. To the contrary in fact and this leads to the next stages of reality, those beyond reality 6. 

These will be tackled shortly, but first why and how these came about will be addressed, since it is both interesting and key to grasping what we believe.  

Adpatation of the Luckiest - Why does it matter? Reason 1 - No Creator

Why does it matter what mechanisms drive evolution?

There are two main reasons.

The first is that many of questions "why" and "how" have their answers routed in reality 2 and concern the hows/whys of life itself. 

To answer these requires an understanding of how life came to be about. And that in turn requires accepting that a lot of what we see happened just because of the interaction between the basic rules of reality 1, the evolution that governs reality 2 and luck. 

The richness of life is so wondrous that it can be hard to see this. It seems so intricate and complex that there "must" have been some higher purpose behind it, there "must" have been a "creator". This has been the majority viewpoint throughout history and still remains the opinion of the majority of people today.

Clearly if such a "creator" exists questions of why and how have very different answers. Well Adaption of the Luckiest renders such an omniscient omnipotent entity redundant. Life can do very well on its own thank you.


Thursday, November 26, 2015

Survival of the Fittest > Adaption of the Luckiest

All in all then the phrase "survival of  the fittest" is quite inappropriate to summarise evolution. 

Far more accurate would be "adaption of the luckiest".