Genetics, Ecology, and, Evolution of Species

From the Lecture Series: Redefining Reality: The Intellectual Implications of Modern Science

By Steven Gimbel, Ph.D., Gettysburg College

When Charles Darwin said individuals do not evolve, but species do, many people did not get what he meant. Individuals slowly change due to the evolution of species, and new generations become different from their ancestors of, say, 200 generations back. What carries the changes? And, what is needed for the changes?

A group of chimpanzees walking, some upright like humans, across a dirt road.
The evolution of species makes individuals diverge from their shared ancestors and become new creatures. (Image: CherylRamalho/Shutterstock)

Darwin changed the worldview of science and the picture of reality. His theory of evolution was the foundation for genetic and ecological theories that followed after his ideas sank in the realm of science.

Aristotle and Carl Linnaeus

Before Darwin’s theory of evolution, there was no well-organized structure for species. In fact, species were not recognized as they are today. Aristotle believed that all living creatures had souls. Thus, taxonomy showed which animals had common parts of their soul.

Linnaeus believed God’s creation went beyond the Great Chain of Being in which all things could be ordered from the least divine to the most divine. He believed in a Divine Plan understanding whose structure details were the key to understanding the Creation.

Darwin brought about the idea that species emerge, change, and split. Then, the old taxonomies lost their previous sense.

This is a transcript from the video series Redefining Reality: The Intellectual Implications of Modern Science. Watch it now, on The Great Courses Plus.

The Family Tree

If two species share a common ancestor, they are of the same category. If they are in the same genus, their common ancestor is not so far back. If they share only a class, then their common ancestor belongs to a very long time ago in evolutionary terms. This taxonomy was a record of development—the family tree.

Miniature of the theory of evolution of man.
Darwin’s theory explained how two species can be traced back to a common ancestor and how far back that ancestor could be. (Image: Sarfina Portrait/Shutterstock)

In this family tree, everything was viewed at the species level. Individuals did not evolve, but the evolution of species made them slowly diverge from their ancestors. Only things that exist as an entity can change and evolve. Then, is species an entity?

Learn more about the origin of life.

The Reality of Species

Species are, in fact, independent entities that can change when individuals do not. They are a part of reality, regardless of the individuals who make them up. They are emergent entities with “emergence”, meaning a non-reducible entity that has parts that do not share the properties of the whole.

With the view about the unity of science, everything ended up as being physics. Thus, understanding the theory of everything would suffice for understanding the whole reality and all disciplines of science.

On the contrary, the founding idea of emergent entities is that knowing all the entities that make up a whole does not necessarily lead to understanding the reality of that whole. Reality has levels. For example, understanding organisms is not possible without understanding genetics. But genetics alone is not enough and must be accompanied by ecology.

Genetics and Ecology

Understanding things at a molecular level might be necessary to answer some big-scale questions. But it is not enough. Looking at the molecular level would never provide the relevant insight for understanding how two species diverged from the ancestor.

The same applies to humans and different entities in a human society. For example, a football team exists as an entity that one can support. The players might change, the team owner might change, and the coach might change as well. Yet, the team is the same entity as a whole and can hold the same fans, even if they hate some of the individual players.

Corporations are also people, from this point of view. They can own properties and make decisions that not all the individuals agree with. For example, if there are two options, and the board goes for a third just because it is slightly better and logical, the board members might still not like the idea. They might not even accept it as a real solution, but they have no other choice. Thus, the board makes a decision that the members do not really approve of.

Learn more about social progress.

Evolution of Species until Sociology

Just as a corporate is an evolving entity independent of its members, the species evolve, too. When human societies were formed, and entities like teams and boards emerged, their legal aspect gained importance, too.

A close up of the definition of the word sociology in an English dictionary.
Sociology was a term coined in 1838, and is the newest discipline of science in our modern world. (Image: ABEMOS/Shutterstock)

Emergence makes its most important debut in science in the birth of the youngest of the scientific disciplines: sociology. In 1838, Auguste Comte coined the term “sociology” to create a foundation for this new science.

Comte believed that society progressed through three phases: religious, metaphysical, and scientific. The first explains how everything is a result of the will of God. The second, the Divine consciousness, is replaced with unseen forces. The third one is where people stop asking, “why?” and try to learn “how?”

Thus, the evolution of species brought humans to the third phase of sociology and becoming more science-oriented.

Common Questions about Evolution of Species

Q: Do individuals evolve?

Individuals do not evolve; species do. It is the evolution of species that makes individuals what they become eventually.

Q: What are emergent beings?

Emergence refers to a non-reducible entity that has parts that do not share the properties of the whole. Species are emergent beings, so the evolution of species is made possible.

Q: Are human societies separate beings from their members?

Yes. A human society is a separate entity from its individual members. For example, a team’s identity does not depend on the individuals playing in it. Otherwise, the evolution of spices would not be possible.

Q: What did Auguste Comte do?

Auguste Comte coined the term “sociology” in 1838 and discussed a general science of culture. He pioneered sociology and contributed further to explaining how the evolution of species happens.

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