Persuasion Machines
A review of Richard Dawkins’ The Extended Phenotype

 PRL Guest Post by Robert Sherwood


Most books on persuasion are written as how-to manuals. They may include information about social science research to explain why persuasion techniques work, or may include information about history’s greatest persuaders. Primarily, though, persuasion books are made to help you use or resist persuasion techniques.

Everyone's unique DNA is passed down from generations before. Image "dna security system" by jon jordan.
Everyone’s unique DNA is passed down from generations before. Image “dna security system” by jon jordan.

The Extended Phenotype, by British evolutionary biologist Richard Dawkins, is not like those books. It’s not about persuasion at all. It’s a book about evolution. It certainly won’t help you get rich or get laid. Still, if you’re interested in understanding the evolutionary history of persuasion, it’s a fascinating read.

Extended Phenotype (cover)
The Extended Phenotype, 1982

The Extended Phenotype argues that organisms have evolved to manipulate their environment, including other animals in their environment. According to Dawkins, manipulating other animals in your environment is as key to natural selection as sharper teeth or warmer fur.

“Genotype,” “Phenotype,” and “Extended Phenotype”

Every living thing on earth has DNA. DNA is your body’s chemical blueprint. It’s responsible for guiding the process of replication for the individual cells in your body.

At the lowest level, DNA is composed of just four molecules, abbreviated by scientists as  “G,” “A,” “T,” and “C.” These four molecules are repeated in different sequences to create “genes.” Genes are chemical recipes for individual proteins in your body. The proteins combine to form tissues, which make up organs, and so forth. In addition to genes that produce proteins, parts of your DNA tell individual cells which proteins to produce to become bone cells, heart cells, brain cells, etc. The entire DNA sequence for a specific individual is called their “genotype.”

When the genotype does its work, it produces a living creature. The features of the creature that are determined by the genotype are collectively named the “phenotype.”

For example, a part of your DNA determines your eye color. This is part of your “genotype.” Your eyes, with their genetically determined color, are part of your “phenotype.”

Because your DNA defines the structure of your body, “phenotype” has been used interchangeably with “physical features of your body.”

The thesis of The Extended Phenotype is that DNA also encodes the brain and other organs that influences behavior. Dawkins believes that the definition of “phenotype” should be extended to include behaviors and interactions, not just physical features.

“The Extended Phenotype” In Action

To support the thesis, Dawkins starts with the humble spider. There are a few species of “social spiders,” but most spiders are solitary hunters. They never interact with other members of their species, and some do not even raise their young. Spiders lay eggs, and then die or leave. When the eggs hatch, the spiderlings extend a strand of silk from their spinnerets and take to the breeze. From that time on, except when mating, spiders are indifferent or hostile to members of their own species.

This is important, because for these spider “socialization” or “education” never happen. The only way to transmit behaviors across generations is to encode them in the DNA. Tweet This

Different spider species have very distinctive types of webs. Dawkins observes that spinning a web is a very complex behavior. Yet most spiders never meet another member of their species to learn this behavior from.

Varieties of spider webs. The technique is passed from one generation to the next via genetic encoding. Image from, CC-By-4.0

Dawkins convincingly argues that the spider’s web is part of their “extended” phenotype. The genes can’t encode a web shape directly, but they can (indirectly) encode the steps the spider takes to weave the web. This web spinning behavior is subject to natural selection, as much as their coloration or body shape.

Next, Dawkins asks whether animal behaviors can be genetically determined or influenced in species with more complex social structures. Does child-rearing and socialization eliminate the effects of genes on behavior?

Dawkins presents the case of the Black-headed Gull. These birds have a very curious routine. As soon as one of their chicks hatch, the parent bird throws all of the egg shells out of the nest. Could this behavior have some survival advantage?

"Black headed Gull bw" by Tony Hisgettt, Flickr, CC-By-2.0
“Black headed Gull bw” by Tony Hisgettt, Flickr, CC-By-2.0

As it happens, it does. Crows can see the bright egg-shell pieces against the darker nest. Since newborn chicks are low in carbs, high in protein, and utterly defenseless, a crow will swoop down to attack any nest where there are signs that chicks may have recently hatched. Researchers confirmed that nests with shell fragments in them were more frequently attacked. The clear implication is that gulls who exhibit the behavior will lose fewer offspring on average to crows. More surviving offspring means that natural selection favors this behavior.

Interestingly, researchers were able to get gulls to throw any brightly colored objects out of their nests, but only if the brightly colored objects were the same color as gull eggs. Gulls were less likely to throw things out of their nests if they were bright red or blue, even though those colors also attracted crows.

Dawkins points out that no “gene for eggshell removal” had been identified, and that there was no direct evidence that birds that remove more eggshells would have children that remove more eggshells. However the circumstantial evidence based on the evolutionary benefit is compelling.

Arms Races and Manipulation

At this point, the book gets interesting for students of persuasion. Dawkins restates a few key premises:

  • The theory of evolution states that animals that are best adapted to their environment leave more offspring. Animals that produce more offspring displace and eventually replace less well adapted animals.
  • “Adaptations” include inherited behaviors that help an animal to manipulate their environment better than competitors.
  • The “environment” isn’t only terrain, weather, predators and prey, etc. The animal’s environment includes other animals of the same species.

Combining these ideas gives us a key concept for persuaders:

A more persuasive animal has an evolutionary advantage over a less persuasive animal.

At this point, Dawkins reminds us of the concept of the “evolutionary arms race.”

“One lineage will tend to evolve adaptations to manipulate the behavior of another lineage, then the second lineage will evolve counter-adaptations.”

This leads us to another key concept for persuaders:

An animal who can resist persuasion has an evolutionary advantage over an animal who is less resistant to persuasion.

Over time we become better liars, and we become better at detecting liars. Over time we become better at manipulating other people’s emotions, and we become better at resisting emotional manipulation.

The Evolution of Persuasion Machines

In Influence, Robert Cialdini’s master work on persuasion, he identifies key reflexes that “compliance professionals” use to trigger what he calls “click-whirr” responses in their subjects. These responses work on us because a successful moist robot is also a successful persuasion machine. We have evolved to persuade, and to resist persuasion. After billions of years of evolution, the least charismatic person you’ve met is a subconscious master of persuasion.  They only seem bad at persuasion in contrast to the master persuaders that you’ve met.

The key takeaway for students of persuasion from The Extended Phenotype is this: persuasion and manipulation are key survival tool for all animals, including human animals. We are all persuading and manipulating all the time. Not using manipulation is not an option for you, or for anyone else.

Realistically, your only options are:

  • Develop an internal moral compass that ensures that you use your powers for good, as much as possible, and
  • If you’re going to persuade anyway, you may as well be as effective a persuader as possible.

To do both, keep reading the books on the Persuasion Reading List, and keep following the Persuasion Reading List blog, to discuss and refine our persuasion techniques.

© 2017 Robert Sherwood

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