"Teleonomy in living systems: an overview" or is Teleology back due to Lamarck's Epigenetics?


Colin Pittendrigh coined the term "teleonomy" in 1958 to describe the goal-directedness of living systems. He distinguished teleonomy from teleology, which he defined as the belief that living systems are purposefully designed by a creator. Pittendrigh argued that teleonomy could be explained by natural selection, without the need for any supernatural intervention.

Pittendrigh's notion of teleonomy has been influential in evolutionary biology. It has been used to explain a wide range of phenomena, including the evolution of adaptation, the development of behavior, and the timing of life history events.

One of the key features of teleonomy is that it is historical. Living systems are not simply designed to achieve a particular goal, but they are also shaped by their past history. This history includes the evolutionary history of the species, as well as the individual's own developmental history.

Here are some proposed examples of teleonomy:

  • The evolution of the eye: The eye is a complex organ that is well-designed for detecting light. However, it did not arise fully formed. Instead, it evolved gradually over millions of years, starting with simple light-sensitive cells.

  • The development of behavior: Many behaviors, such as nest building and migration, are complex and goal-directed.

  • The timing of life history events: The timing of events such as reproduction, growth, and death is also influenced by teleonomy. These events are not random, but they are timed to maximize the individual's fitness.

Epigenetics is the study of how changes in gene expression, or how genes are turned on or off, can be inherited without changing the DNA sequence. These changes can be caused by environmental factors, such as diet, stress, or exposure to toxins, and can last for generations.

Epigenetics furthers the view of teleology. Teleology is the belief that there is a purpose or goal to life, and that things happen for a reason. Epigenetic studies have shown that genes can be turned on or off by environmental factors, which can have a profound impact on an organism's development and behavior. This suggests that there is a purpose to life, and that organisms are not simply the product of random chance ie NeoDarwinism 

Studies suggest that our genes are not our destiny. We can influence our gene expression by controlling our environment, and we can use this knowledge to improve our health and well-being.

Teleology is the belief that organisms are designed with a purpose or goal. In the context of epigenetics, teleology can be seen as the idea that environmental factors can influence the expression of genes in a way that helps an organism survive and reproduce.

Teleology and teleonomy are two different ways of understanding the goal-directedness of living things. Teleology is the belief that living things are designed with a purpose in mind, while teleonomy is the belief that living things appear to be goal-directed because of their evolutionary history.

In teleological explanations, the purpose of a living thing is seen as being caused by a conscious agent, such as a god or a designer. For example, a teleological explanation for the eye might be that it was designed by a god to see.

In teleonomic explanations, the purpose of a living thing is seen as being caused by natural processes, such as evolution. For example, a teleonomic explanation for the eye might be that it evolved over time to help animals see better.

Teleology is often associated with religious beliefs, while teleonomy is associated with scientific explanations. However, it is important to note that teleology and teleonomy are not mutually exclusive. It is possible for a living thing to have both a teleological and a teleonomic explanation. For example, the eye might have been designed by a god, but it also evolved over time to help animals see better - theistic evolution.

The distinction between teleology and teleonomy is important because it helps us to understand the nature of living things. Teleology suggests that living things are special and different from non-living things, while teleonomy suggests that living things are simply complex systems that have evolved to be goal-directed.

In recent years, there has been a growing movement in biology to replace teleological explanations with teleonomic explanations. This is because teleological explanations are often seen as being unscientific and unfalsifiable. For example, it is impossible to prove or disprove that the eye was designed by a god.

Teleonomic explanations, on the other hand, are testable and falsifiable (not). For example, we can test the hypothesis that the eye evolved over time by looking at the fossil record and by studying the development of the eye in embryos.

Except the eye developed over one hundred times with no evolutionary history. The first was in trilobites that suddenly showed up in the Cambrian.

The shift from teleology to teleonomy has been the crux of Darwin's theory 170 years ago.

So what's the fuss? "If it quacks like a duck!?"

Article snippets:

Teleonomy in living systems: an overview

https://doi.org/10.1093/biolinnean/blad037

03 June 2023

Abstract

The introduction offers a brief account of the origin of Colin Pittendrigh’s notion of teleonomy, in many ways comparable to Dobzhansky’s later proposal of ‘internal teleology’, and a subsequent externalist interpretation of the concept by Ernst Mayr which, unfortunately, has remained influential.

As part of the growing movement that places organismic purpose, goal-directedness and agency back at the centre of biology

These papers represent scientifically founded views of evolutionary biologists and philosophers of science who seriously question the adequacy of the neo-Darwinian Modern Synthesis to account for the purposive nature of living systems

Like any other phenomena associated with life, purposive and teleonomic behaviours demand evolutionary explanations and context

Without any recourse to supernatural or non-material processes, various approaches to trying to understand how this goal-directed, teleonomic property of life has influenced the course of evolution are explored



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