Sometimes a good idea just keeps getting rediscovered. The eye has evolved many times independently, and parasitism has evolved for no less than 60 times. This is called convergent evolution. And of course, it has its evil twin... divergent evolution.
Consider this picture below, of the complex shapes of closely related species of Bombus (bumblebees). These species are so similar that the main way to distinguish them is by looking at their penises...
Source: The Evolution of Primary Sexual Characters in Animals, Figure 4.1
This post is supposed to be a prequel to my upcoming post on the major transitions in the evolution of life on earth. Eörs Szathmáry is a good lecturer and the lecture gives a very clean overview of the origin of self-replication, evolvability, and the relation of evolution with learning theory. I am reading about this, because I think AI might cause another major transition in evolution in a similar way.
This post will give annotations, references, and comments, to read along the lecture.
These seminars would begin $10^{10}$ years ago with the origin of the universe, then move on to the beginnings of biological life $10^9$ years ago, and so on, up to the development of modern human society in the present time, or $10^1$ years.
In The Future of Human Evolution (2004), Nick Bostrom argued that there are two possible ways for future evolution of humans to result in a bad end for humans, because what end up being evolutionarily fit is not "nice". Two possible bad outcomes:
Scenario I: The Mindless Outsourcers.
Competitive uploads begin outsourcing increasing portions of their functionality: “Why do I need to know arithmetic when I can buy time on Arithmetic-Modules Inc. whenever I need to do my accounts? Why do I need to be good with language when I can hire a professional language module to articulate my thoughts? Why do I need to bother with making decisions about my personal life when there are certified executive-modules that can scan my goal structure and manage my assets so as best to fulfill my goals?” Some uploads might prefer to retain most of their functionality and handle tasks themselves that could be more efficiently done by others. They would be like hobbyists who enjoy growing their own vegetables or knitting their own cardigans; but they would be less efficient than some other uploads, and they would consequently be outcompeted over time.
We can thus imagine a technologically highly advanced society, containing many sorts of complex structures, some of which are much smarter and more intricate than anything that exists today, in which there would nevertheless be a complete absence of any type of being whose welfare has moral significance. In a sense, this would be an uninhabited society. All the kinds of being that we care even remotely about would have vanished.
The link between mutations and cancer had been proposed very early, at the beginning of the 20th century, by Theodor Boveri. He conceived the origin of cancer as the abnormal distribution of chromosomes during cell division, provoking a regression of the cell to an uncontrolled, egoistic behaviour (Boveri 1914).
The idea that cancer cells were unregulated cells that had escaped any control by the body was clearly at odds with the model that tumour cells evolve as organisms do. Once again, cancer was seen as the return to an ancestral, uncontrolled state, not the result of an open evolution.
This opposition probably explains why Wilhelm Roux did not propose an evolutionary model of cancer in his 1881 book on the fight of the parts within organisms (Roux 1881, 2012). This book was immediately well received, but rapidly forgotten. Roux proposed that a struggle between the different parts of the organism – molecules, cells, tissues and organs – took place during development. Somehow, he extended Darwinian competition to what happened within organisms during development. This competition of the different parts of the organism for resources was essential for the optimization of physiological adaptation.
Basically, Wilhelm Roux thought that in the development of a single body, the parts of a body are fighting over resources, just as bodies fight over resources in an ecosystem. The result of this (well-organized) fight is a fine and optimized body.
Since tumours also compete for food with the rest of the organism, it might have seemed appropriate to include them in the picture. Roux did not, because he considered that these cells had embryonic characteristics... and were utterly unregulated. Their behaviour could not be compared to the well-regulated competition that took place during the development of organisms (Roux 1881, 2012, p 69).
Atavism: a return to the ancient past, in behavior, appearance, or genes. From Wikipedia:
Evolutionarily traits that have disappeared phenotypically do not necessarily disappear from an organism's DNA. The gene sequence often remains, but is inactive. Such an unused gene may remain in the genome for many generations. As long as the gene remains intact, a fault in the genetic control suppressing the gene can lead to it being expressed again. Sometimes, the expression of dormant genes can be induced by artificial stimulation.
That sounds like computer code with a long legacy where an ancient feature pops up for no apparent reason.
Atavisms have been observed in humans, such as with infants born with vestigial tails. Atavism can also be seen in humans who possess large teeth, like those of other primates. In addition, a case of "snake heart", the presence of "coronary circulation and myocardial architecture [which resemble] those of the reptilian heart", has also been reported in medical literature.
I've heard of people with tails before, but snake heart?? That's new!
Cancer is when a small group of cells in the body goes feral and stops playing the multicelluar game with its neighbors. This can be viewed as a kind of antisocial break from a cooperative society, or a new species arising in an ecological environment. This post examines many aspects of cancer from an evolution point of view.
I am very interested in cancer as a good example of "unwanted evolution" that humans are wrestling with. Other unwanted evolutions include evolution of drug resistance, herbicide resistance, etc, but cancer stands out as being remarkably complex and different.
Every human cell in your body is a direct descendent of eukaryotic cells that lived and fended for themselves for about a billion years as free-swimming, free-living little agents... They had to develop a lot of self-protective talent to do that. When they joined forces into multi-cellular creatures, they became domesticated. They became part of larger, more monolithic organizations... We don't have to worry about our muscle cells rebelling against us, or anything like that. When they do, we call it cancer.
This is my wild idea, maybe only in humans, and maybe only in the obviously more volatile parts of the brain, the cortical areas, some little switch has been thrown in the genetics that makes our neurons a little bit feral, a little bit like what happens when you let sheep or pigs go feral, and they recover their wild talents very fast.
He proceeded to explain how our neurons, by being a little bit wild and risky, give us intelligence, creativity, and mental diseases. It's interesting (despite being extremely speculative) and worth a read, but not relevant to this post.
In 2030s, the humans arrived on Mars. Humans were born on land, and they had lungs that could not extract the gas that humans need to continue their chemical life-fire. Not a problem. They brought with them cylinders of compressed life-gas, and life-gas producing creatures. They turned Mars green and covered its surface with life-gas.
In 19th century, metallic horses were born on earth, and they had circular feet that could not trot over most kinds of land. No mountains, no grasslands, no marsh. Only hard flat surface of no more than 10 degrees in slope. Not a problem. Their human companion-species set out and terra-reformed the world for them. Now there are 10e10 of these metallic horses running wild on the hard flat surfaces over earth.
Consciousness is not mysterious, it’s just the brain describing itself—to itself.
Michael Graziano is a professor of psychology and neuroscience at Princeton University. His style of explaining consciousness is fully materialistic:
The hard problem of consciousness doesn't exist, because consciousness is an illusion.
The real problem is just this: Why do humans proclaim "I'm conscious."? What do they mean by that, and what made them proclaim that?
The answer is that the illusion of consciousness is a byproduct of human evolution.
Basically, consciousness is an illusion, a spandrel of evolution.
Most Popular Theories of Consciousness Are Worse Than Wrong (2016), Michael Graziano. In this essay, he shoots down multiple theories of consciousness, because they don't answer the real problem. For example, concerning the Integrated Information Theory:
What exactly is the mechanism that leads from integrated information in the brain to a person who ups and claims, “Hey, I have a conscious experience of all that integrated information!” There isn't one.
In order to figure out why humans have this illusion, it's necessary to study humans as fully physical (no funny qualia business plz) robots that think about themselves but in a grossly inaccurate way:
The theories that show the most promise are metacognitive theories... the brain doesn’t just model concrete objects in the external world. It also models its own internal processes. It constructs simulations of its own cognition. And those simulations are never accurate. They contain incomplete, sometimes surreal information. The brain constructs a distorted, cartoon sketch of itself and its world. And this is why we’re so certain that we have a kind of magic feeling inside us.
The origin of consciousness: we think about own thoughts in grossly simplified models.
This post is heavily based on Tim Tyler's page. It has lots of dead pictures, so view them on the Internet Archive if you see them.
Genes are not the only thing that can copy themselves. Computer virus, RNA, protein virus (prion), and chain mails, they all can.
The idea of non-gene replicators is not new. Richard Dawkins proposed memes in The Selfish Gene (1976), and Graham Cairns‑Smith proposed clay-genes (clenes?) in The origin of life and the nature of the primitive gene (1966). Genes and memes are getting all the popularities, but clenes aren't, so I'll summarize clene theory. A detailed explanation is here.
Overview of clenes and genes
First we check the 1966 paper's abstract:
Life on earth evolved through natural selection from inorganic crystals.
During the formation of a crystal, certain kinds of lattice imperfections usually replicate as a necessary part of the crystallization process.
... the primitive genographs were patterns of substitutions in colloidal clay crystallites. (The theoretical information density in such a crystallite is comparable to that in DNA.)... A gradual “take-over” of the control machinery by organic macromolecules—a genetic metamorphosis—is then considered to have occurred.
Let's start with one death. Pristionchus pacificus eating a Caenorhabditis elegans.
Pristionchus pacificus is a nematode that can eat many kinds of foods. In this video, it uses a small tooth to puncture the cuticle of its prey, then sucks in the contents.
The Celens (imma call C elegans that) come in two sexes: male and herm. Herms contain only about 300 sperm cells, after using them all, the herm cannot fertilize more eggs, unless it gathers more from mating with a male. Males cannot reproduce on their own and must mate with a herm to produce offsprings.
