So Ray Comfort is now complaining on the revered pages of the respected publication, World Net Daily about me. The article is full of dishonest misquotes, but let’s zip right to Ray’s scientific misunderstandings. They are deep and painful. He has this bizarre idée fixe that the necessity of every species having males and females somehow greatly reduces the probability that new species could arise. It’s total nonsense, and I dismissed it briefly when I commented on it before.
“I know Ray is rather stupid, but who knew he could be that stupid. This has been explained to him multiple times: evolution does explain this stuff trivially. Populations evolve, not individuals, and male and female elephants evolved from populations of pre-elephants that contained males and females. Species do not arise from single new mutant males that then have to find a corresponding mutant female – they arise by the diffusion of variation through a whole population, male and female.”
Ray has read that, and failed to grasp the central concept. Take a look at the workings of Ray Comfort’s mind as he attempts to wrestle with a simple idea: the hamster wheel is wobbling, but the poor beast lies dead with legs up in its cage, and nothing is turning over.
Comfort replied, “I don’t have the evident faith the professor has to believe in the theory of evolution, and so I am glad that he took the time to explain his beliefs as to why females had evolved along with males in every species in creation.
“Okay, I’ve got it,” Comfort continued. “Your belief is that species do not arise from single new mutant males that then have to find a corresponding mutant female. So, let’s take it slowly for those of us stupid folk who like empirical evidence. We are looking at a contemporary male and a female elephant. They are part of a population of elephants. Let’s go back to their elephant ancestors 10,000 years ago. They are still male and female elephants (they had to be because that’s how elephants reproduce). Let’s now go back one million years to what you called ‘the populations of pre-elephants that contained males and females.’ Obviously, they are still male and female way back then because that’s how pre-elephants reproduced,” Comfort said.
“Let’s go back even further (100 million years ago) to pre-pre-elephants that also contained males and females. At what point of time in evolutionary history did the female evolve alongside the male? And why did she evolve? Then explain, if you would professor, why horses, giraffes, cattle, zebras, leopards, primates, antelopes, pigs, dogs, sheep, fish, goats, mice, squirrels, whales, chickens, dinosaurs, beavers, cats, human beings and rats also evolved with a female, at some point of time in evolutionary history. Professor, I know you believe, but please, give us who are healthy skeptics some empirical evidence. Remember, stupid people like me want good hard evidence before we, like you, become believers in Darwin’s theory,” Comfort said.
No, Ray, you didn’t get it. You still don’t get it. You’ve completely missed the point.
All elephants reproduce sexually. All elephant ancestors back into the paleocene reproduced sexually. All mammals reproduce sexually. Our vertebrate ancestors reproduced sexually. This is not a trait that evolved recently — it’s an ancient property inherited for generation after generation, and as long as you are talking about elephants or mammals or any of the creatures that seem familiar to you, you aren’t talking about the evolution of sex — that occurred long ago. So let’s set sex aside for a moment and think about what actually did evolve in elephants.
Here’s the phylogenetic tree for recent species of elephants.
About 7 million years ago, there was one species of elephant that was distinct from the modern forms, but that was ancestral to the African elephant (Loxodonta), the Asian elephant (Elephas), and the now-extinct mammoth (Mammuthus). Let’s just focus on what happened 7 million years ago for now.
A speciation event occurred. This does not mean, as Ray seems to think, that an African elephant gave birth to an Asian bull calf, that then wandered off forlornly to find a female Asian elephant. There was a large population of these ancestral elephants and they split — a group in one area or environment was breeding largely within its own group, while a group in another area was breeding largely within its group. They could have been isolated by geography, or by the emergence of a genetic isolating mechanism, but either way, you wouldn’t have been able to tell them apart if you had a time machine and were right there. These populations — populations, not individuals — lived and bred and died apart from each other, and gradually enough variations accumulated that we could tell them apart; the Asian elephants had smaller ears than the African, for instance.
This took time, millions of years, and at no point in that time were the populations reduced to a single, lonely male. What we’re talking about is the slow divergence of groups of animals over many generations, and these groups always had many males and many females.
In the case of elephants, we also know what kinds of mechanisms could promote that divergence: distance. Elephants in their heyday had a worldwide distribution, and a bachelor bull in Africa could not write off to Indonesia for a bride — he bred with the local African females, and the Indonesian females bred with the local Indonesian males. Isolation in space would allow differences to grow.
We also know that elephants were a diverse group with hundreds of species, most of which have gone extinct. The elephant ancestors that lived 50 or 100 million years ago would probably not be recognized as elephants by someone like Ray — once upon a time, they looked more like large pigs with especially prominent snouts and tusks.
And back in the mesozoic origins of the clade, the elephant ancestor would have probably looked more like their extant cousins, the hyraxes…small, and looking like a stocky rodent. Hyraxes have males and females, as did the ancestral population that gave rise to hyraxes and elephants.
If we go even further back to the common ancestor of horses, giraffes, cattle, zebras, leopards, primates, antelopes, pigs, dogs, sheep, goats, mice, squirrels, whales, beavers, cats, human beings and rats, we’d find a population of male and female mammals.
Further still to the common ancestor of chickens, dinosaurs, and mammals, we’d find a population of male and female reptiles.
Yet further to the common ancestor of modern fish and reptiles, we’d find a population of male and female fish.
All of these diverse modern groups are the product of the divergence of multiple populations from a common ancestral population.
Is it sinking in yet?
Evolutionary biology is always dealing with changes in populations.
Now what about the issue of sexual reproduction that troubles Ray so much?
First, let’s clear one thing off the table: males and females do not represent separate evolutionary phenomena. I know, that seems like it ought to be obvious, but one shouldn’t take anything for granted in a discussion with people like Ray. Men and women are essentially identical in their genetic complement — with very few exceptions, we carry the same suite of genes — and all of the obvious differences are the result of simple switches. A female embryo can be induced to develop into a male by the presence of the appropriate hormones, and a male embryo can be born looking female with the right blockers or receptor errors.
As for the appearance of those male and female sexes, their origin lies far back in the pre-Cambrian. The differences arose gradually. The distant ancestor of all those animals Ray rattled off, and including insects, clams, squid, starfish, and leeches, was a pre-Cambrian worm, and it was most likely a hermaphrodite, producing both sperm and eggs. The sexual differences Ray finds so difficult to comprehend arose by progressive specialization: genetic switches that could turn off either male or female gamete production were already present, and some individuals in the population turned off the making of eggs and made sperm, while others did vice versa. It happened in worms, worms that have contemporary relatives that live fruitful lives of sexual ambiguity.
I teach freshman students who have no problem at all in understanding these basic principles. I’d recommend that perhaps Mr Comfort could try taking a biology class someday, but I doubt that he could pass one…and I feel too much pity for any instructor he might have.
Rohland N, Malaspinas A-S, Pollack JL, Slatkin M, Matheus P, Hofreiter M (2008) Proboscidean Mitogenomics: Chronology and Mode of Elephant Evolution Using Mastodon as Outgroup. PLoS Biology 5(8):e207 doi:10.1371/journal.pbio.0050207.
Shoshani J (1998) Understanding prooscidean evolution: a formidable task. TREE 13(12):480-487.
Shoshani J, Walter RC, Abraha M, Berhe S, Tassy P, Sanders WJ, Marchant GH, Libsekal Y, Ghirmai T, Zinner D (2006) A proboscidean from the late Oligocene of Eritrea, a “missing link” between early Elephantiformes and Elephantimorpha, and biogeographic implications. Proc Nat Acad Sci USA 103(46):17296-17301.