For the last few years, I have been thinking a lot about natural selection, a concept that Charles Darwin proposed in his book On the Origin of Species (1859) as a mechanism of evolution. Natural selection has three essences: competition, selection, and adaptation. The key point is that these words target a population but not individuals. Competition, selection and genetic adaptation in a population. In general, genetic adaptation is the consequence of consistent selection in a population, and selection is the consequence of consistent competition in a population. Without competition, selection and genetic adaptation do not exist conceptually.
In the foundation of this idea, there is a view that an environment where each species lives does not provide enough resources to support everyone. The survival of each individual depends on their intrinsic ability (i.e. fitness) to compete for the resources. All others in the same species are not your friends but competitors of the resources for survival.
How good do you need to be? Where is the line between death and survival? Does only the top 10% survive? Or the top 90%?
The survivors are considered the winners of the competition in natural selection. The current survivors are selected through past resource competitions within their environment because they had better intrinsic fitness than non-survivors.
The reason for survival should be genetic to link this selection to genetic adaptation. Genetically controlled phenotypic traits determine whether individuals can win or lose in competition. If the phenotypic traits are not caused by genetics, such as differences in nutrient conditions, selection and genetic adaptation cannot be linked.
In this sense, the type of competition is important. For natural selection to occur, competition should be based on genetically controlled phenotypic traits. Genetic factors should be the determinant of winners or losers.
In addition, the type of competition and selection criteria should be consistent in space and time for genetic adaptation. Every competition should be based on the same genetically controlled traits with the same selection criteria. A whole population should go through them. If there are a selected population and a non-selected population, and they can be mixed, no genetic adaptation occurs. This also happens when two populations are selected but with different selection criteria. Uniformity in a whole population and consistency in each round of competition and selection are essential for successful genetic adaptation.
My question is if this happens in nature.
I agree that the resources are not sufficient to support everyone. However, they are sufficient to ensure the continuity of each current species. This is why we see many species now, although many are in danger of extinction.
If there are not enough resources for everyone, does competition need to happen in nature?
Before I dive deep into the topic, I propose that there are two types of resources: global/uniform resources and opportunistic resources. The first type is relatively uniform and ubiquitous, like oxygen and global climate. It is available to everyone with little effort, and no one competes for it. The second type is opportunistic and probabilistic. Food and mates, as well as predators and weather, are this type.
In essence, each opportunity is a once-in-a-lifetime encounter. This does not mean that each opportunity is special. Every moment is a once-in-a-lifetime moment, never repeated in an identical way. Each encounter is unique and unpredictable.
Many near misses. A life-changing encounter can happen or not happen due to a one-minute difference or one corner away.
Is it possible to compete for opportunistic and probabilistic resources? This is only possible for humans but not others.
You may say that animals compete for their food and mates. I agree. However, this competition is not competition in a population but duels. A duel of two (or three) individuals. Do the losers have no chance of food or a mate? Of course, they do. Because where you find food or mates in time and space is not fixed; it is unpredictable. The next day, a former loser may find food and a mate at a different place. Then, is the winner of a duel due to genetically controlled phenotypic traits? No guarantee. No need to be. I think most if not all, sexual selection is selecting epigenetic phenotypes like nutrient conditions. It is not based on competition in a population but on spontaneous duels of individuals. The duels and non-genetic trait selection have no power on genetic adaptation.
Opportunistic and probabilistic resources are local and temporal. The distribution pattern of opportunity frequency is uneven and inconsistent in space and time.
The existence of one current species means the opportunity frequency in the past was sufficient to sustain it. The ratio of death and survival was good enough to sustain as a species. Death is the consequence of intrinsic genetic dysfunctions (i.e. genetic lethality – albino in nature is one of them) or bad luck. No competition.
Species extinction occurs for two reasons. The first is changes in global/uniform resources, such as changes in oxygen levels or global climate. The survivors are simply lucky because their intrinsic properties are suited to the change. No chance of preparation, but it happens to be suited. This is not the level of variation within a single species but the fundamental differences between distinct species. Think of dinosaurs and mammals.
The second is the reduction in opportunistic and probabilistic resources. The niche/habitat originally supporting the species’ survival disappears, or too many predators. Humans contributed to many extinctions through these two activities. Changing habitats and hunting a lot efficiently. Invasive species are also of this type. They are not competing but simply taking over the niche/habitat the inherent species rely on. The original rich opportunistic and probabilistic resources are robbed. The species cannot adapt but become extinct when the resources they rely on disappear.
Genetic adaptation could occur but should be rare in nature because it demands consistent competition and selection for a whole population. Humans are skilled at manipulating the opportunity frequency and setting up competition and selection in a population—this is the basis of fermentation, agriculture, domestication and most, if not all, laboratory proofs of natural selection. Subpopulations are ISOLATED intentionally or unintentionally. Isolation means their environment is closed – there are no new participants or escapers. Consistent competition and selection become possible, and genetic adaptation is achievable.
In nature, a duel of individuals looks like a competition. However, you don't need to win all the duels. Losing is Okay. Running away from it is also Okay. After all, tomorrow is always another day.
However, humans have an exceptional ability, which is the recognition of the past and future—that comes from language. Without the past and future, the frequency of opportunity cannot be recognized. Humans are the only species that know tomorrow comes. The concept of owning emerged because owning changes tomorrow. We have built consistency as a human society and have a concept of owning beyond consuming. The concept of owning created competition in a population. In other words, humans are the only species living in competition in a population.
The evolution of life is not the consequence of competition in a population. We are just the progeny of someone who did not luckily die.
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