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How Changing Characteristics Is Changing The World And Vice-Versa

Charles Darwin, the father of genetics and evolution, in his book, The Origin of Species, had the subtitle, “Preservation of favoured races in the struggle for life” and that is the crux of evolution and natural selection as a whole. But simplifying the process doesn’t mean a complete absence of complications. With 8.7 million (according to 2020 data) known species of plants and animals on this planet Earth, the process and its results are intricate, with several still beyond human understanding, and an enormous variety of organisms still waiting to be discovered.

Research in evolution has included approaches from different fields of science, ranging from developmental biology, paleontology, ecology, organic chemistry, and many more. Survival of the fittest is the quote, one associate, with evolution the most, and on some level, it’s well within the definition, but there are so many factors to be considered while concluding why a species went extinct and why some survived, and how time involuntarily changes the capabilities and characteristics of organisms to keep it from dying. 

There are a thousand examples over the course throughout history since evolution theory was developed that can support this claim as evidence of species changing its core attributes. But in the recent past, it’s us humans going through the industrial revolution that is to be blamed for the climate change, and depletion of natural resources, which ultimately cause animals to adapt to environmental pressures.

Let us see some examples of this inherent affinity for diversity –

1.    Super Insects

Almost all insects are known for their ability to develop resistance to insecticides and pesticides, which we humans use as a way to save our crops from. Most of the insects are killed due to it, however, certain insects will experience a gene mutation to develop immunity to it and those insects will reproduce.

So, upon exposure to these harmful chemicals, the weaker ones die but the mutant ones develop the resistance gene. They then reproduce very quickly, within a few generations, and since the generation length for insects is short, they evolve into super insect forms of their ancestors.

2.    Flightless Birds

Flightless birds like ostrich, kiwi, penguin, moa, rheas, are known to us as their key characteristic is that they cannot fly, being birds. But that wasn’t the case all along. Flightlessness has evolved in many of these different birds independently.

The first reason is gigantism, which is clear as to when the bird has evolved into large creatures, they are unable to support their body into flight. Another reason is competitive exclusion, which means when these birds didn’t have land-based predators for years, they had no reason to fly, and hence slowly over generations they lost the ability altogether.

3.    Shrimp, Crabs & Mexican Cavefish

There is a phenomenon in evolution called regressive evolution, which is when creatures lose a certain ability when they use it less or don’t need it anymore. That’s what happened with a group of cave-dwelling crustaceans, named Mexican Tetra Fish, and some other shrimps and crabs. These organisms used to have the ability of eyesight, but over several generations, they started living in deep-sea caves underground, where no light ever reaches.

So, upon research scientists found that not only these creatures were going sightless, but also their brain corresponding to eyesight was degenerating. On the other hand, their other senses like control touch, and smell were improving. This goes on to show how their natural environment and changing life conditions perpetuated a complete change of their capabilities.

4.    Peacocks

This one relates straight to Darwin’s time when he was perplexed upon seeing no reason for male peacocks having a brightly colored tail and feathers. But he eventually concluded the reason was sexual selection. So, even though the basic genes in both the male and female species of the peacock family are similar, the genetic switch occurred to make the males inherit this particular trait.

These ancient genetic switches have evolved to manipulate the appearance of animals in a way that favored their selection as mates. And hence to be advantageous in the selection of mates process, make counterparts of species like peacocks develop this trait.

5.    Green/Brown Anole Lizards

This one could be easily categorized as weird because of the simplicity of this change. In Florida, the native green lizards have generally occupied the lower branches and trunks of the trees, but they were in for a surprise when their invasive counterpart native brown lizards made contact. Now faced with double the competition and limited resources, within 15 years and about 20 generations, the green lizards evolved their feet to climb up higher on the trees abandoning their enemies.

Over this astonishingly small period, the green anoles’ toe/limb pads became noticeably larger, with more sticky scales better at gripping the thinner, smoother branches found higher up. This kind of evolution is called character displacement.

6.    Blue Moon Butterfly

In another one of the fastest adaptations to a crisis to save their species are the blue moon butterflies in Savaii. Wolbachia is a bacterial infection that infects arthropods and selectively kills only one sex which effectively leads to population reduction in the whole species as a whole.

So, when this pandemic hit the male blue moon butterflies, within 10 generations and 1 year, they developed resistance to the deadly bacteria, thanks to the few male moths that were immune to breeding. This rapid evolution is a response to extreme population pressures.

7.    Tawny Owls

A recent study conducted by scientists in Finland, indicates some birds are evolving in response to climate change. The tawny owls can be split into two plumage-based categories – brown or grey. Feather color is hereditary, with grey plumage dominant over brown. But according to the research, the number of brown owls was increasing. And as the overall climate of the planet increases and the winters become milder, grey feathered tawny owls are likely to disappear.

The owls are evolving to cope with increasing temperatures through gene mutation at a very slow pace. The weird part is that brown owls have weaker immune systems. It’ll be interesting to see how the gene pools react to these strange climatic conditions.

8.    Deer Mouse

Scientists at Harvard University researched the perfect illustration of natural selection in North American Deer Mice. Thousands of years ago, Deer Mice used to be dark brown colored when they primarily lived in deep woods. However, a small portion of them split away to the deserted sandhills of Nebraska.

These mice evolved over the years and grew lighter in color, to match the color of their surroundings. A single genetic change leads to this lighter coloration. Both the gene pools thrive in their surroundings separately.

9.    Warrior Ants

Warrior ants or Army ants are followers of no conventional evolution theory, as entomologists at Cornell University identified these ants have existed since 100 million years ago and still inherit the same essence of their ancestors. These creatures defy evolution, or maybe they don’t need it. But recently, research showed that these ants have a chemical signal that identifies their colony.

Some groups of ants developed the sense to imitate this signal from another colony, so they can attack a colony and take over. This aggressive act was unseen before, hence was concluded to be the gift of evolution. Also, the worker ants will not even realize there has been an invasion and continue to work.

10. Peppered Moths

This one goes to the birth of the Industrial Revolution in the 1760s, which led to a term called industrial melanism in many species. One of the major affected were peppered moths, as at the genesis, the population of dark-colored moths prevailed as a part of the directional color change, due to the pollution. But subsequently, when the pollution was reduced, the light-colored organisms again predominated, completely agreeing to Darwin’s Natural Selection Theory.

Several theories are accepting and rejecting each other’s hypothesis because peppered moths have been at the center of a lot of unanswered questions that keep on boggling the minds of scientific researchers.

In conclusion, evolution as a theory has been such a knowledgeable experience for humanity and yet somehow, the breadth of evolution’s contribution to research and our daily lives remains grossly unappreciated—and sometimes deliberately denied—in the public realm. Genetics are and will be a part of our planet’s history and no conspiracy theories can deny it because, with evolution, the evidence lies right in front of our eyes, waiting to be investigated.

The only reason why the title uses the word “weird” is that it’s something magical and yet completely logical in its way of change. Evolution as a process will never cease to exist, it is happening in thousands of organisms around you as you read this, but we can hope that its integral role in science for uniting history and future doesn’t go unnoticed.