Why aren't apes evolving into humans? (EvoPsy) (Misconception)

Evolutionary Psychology Lesson #3: Evolutionary Misconception #2:

Introduction

Some skeptics of the theory of evolution think that the theory must be flawed because if it were to make sense you should expect apes, such as our closest relative the chimpanzee, to evolve into human beings which are considered to be the superior species. In the following article, I will be debunking this myth.

The practical impossibility of apes evolving into humans

First off, one has to realize that apes aren’t at a midway point between us and our mammal ancestors, apes branch off from us 10 million years ago, they are not our ancestors, but our cousins, therefore, a great deal of their biological and psychological traits vary to different degree from our common ancestor. Logically speaking it is therefore literally impossible for them to evolve into humans without restarting from scratch since in order to evolve into us they would initially need to lose the traits that differentiate them from us. That backtracking concept of going back into their lineage in the form of our common primate ancestor would completely go against the logic of evolution, thus, it is safe to conclude that is impossible for apes to evolve into humans or into anything of great similarity.

Evolving human-like intelligence

Now that it has been clarified that apes can’t evolve precisely into humans, one might still wonder; since our superior intelligence provided us with phenomenal evolutionary advantages, which led us at the very top of the food chain, why haven’t apes evolved human-like intelligence over time? This question is of greater complexity to answer, but it will leave you again with no ambiguity once understood. In order to answer this question one has to grasp three evolutionary concepts:

1. Has thoroughly explained in the previous blog post, a species evolution can only happen in the form of a slow process of incremental changes.
2. Adaptation(a new evolutionary trait) occur to solve recurrent problems a species is facing in his environment. Therefore if the species is fit for his environment and that environment vastly stays unchanged, the species isn't pressured to develop new adaptations.
3. The development of an adaptation comes at a certain cost, if the cost outweighs the benefit in terms of fitness(ability to survive and reproduce) the species won’t develop that adaptation.

Base on those principles I assume you can already start formulation an idea about why apes aren’t evolving human-like intelligence. One should also come to grasp the idea that the rate under which human beings evolved is nearly historically unprecedented, in terms of evolution we are the exception, not the norm. In fact, some species stay virtually unchanged for millions of years, such as the alligator who is nearly indistinguishable from his 8 million years ancestor. Species don’t need to evolve, if they are to be evolving that process is dependent on the randomness of the interaction between their genotype(genetic constitution of an individual organism) and the environmental challenges it faces. Through thousands of years of evolution, the human brain evolved countless psychological modules that serve different adaptive functions which were fit with the challenges we faced, from this angle, expecting apes to evolve human-like intelligence is actually expecting the improbable.

The reality is that from an evolutionary perspective apes are fine as they are, in the context of their habitat their level of fitness is sufficient enough to keep the species alive, apes didn’t need to evolve in a human fashion way since they didn’t have evolutionary pressure to adapt in that direction. If they were to have selective pressure to change in a different adaptive way, it would actually be extremely unlikely that they were to evolve as we are since evolution takes different forms depending on the environmental challenges a species is facing. Being slightly more human-like intelligent comes at a high energy cost, our bigger brain demands a greater supply of oxygen to function. In the case of apes, one has to ask if an improvement of their mental capability would be worth the payoff when considering that highly nutritious nutrients in the form of fruits are easily accessible in the branches of trees and that they can easily distance themselves from predators by hiding themselves in those same trees. Yes, greater intelligence, such as the ability to communicate as we do, would likely be evolutionary beneficial for apes, but since changes only happens incrementally, when you factor the composition of their current genotype(genetic constitution of an individual organism), having an ever so slightly superior ability to communicate may not be advantageous at the cost of a slightly reorganized or bigger brain. In contrast, for the case of human beings, evolutionary biologists theorize that a subgroup of our common ancestors with apes faced an environment where resources were scarce, consequently in order to survive they were pressured to quickly evolve; in order to reach new sources of food they notably develop the ability to walk upright in order to travel long distances providing them with free hands to carry tools and as another source of food they also heavily accentuate their ability to collaborate in group in order to catch large preys.

All in all, it may seem logical to think of evolution as a linear progression toward greater complexity, but that simply isn’t actually the case. In fact, evolution sometimes go counterintuitively, for instance, our mammals ancestor originated from the sea because it was advantageous for our ancestor to escape the sea full of predators and to conquer the land conversely free of predator, but later on, when the land became full of creatures, some mammals, such as the dolphins and whales ancestors, were pressure to escape the land and return to the sea because the sea was an environment easier for them to survive in. As whales shouldn't expect their closest land mammals relatives to eventually evolve into something similar, there should be no reason to expect apes to evolve in a human-like way.

Previous articles:

Evolutionary Psychology Presentation

Evolutionary Psychology Introductory Presentation

Evolutionary Misconceptions

How evolution could have created the human eye?

If you are interested in more content like this, please give me a thumbs up in encouragement, it would be greatly appreciated! Stay tuned for the next article!