Chapter IV: Natural Selection: Or the Survival of the Fittest

Darwin noticed: “What natural selection cannot do, is to modify the structure of one species, without giving it any advantages, for the good of another species: and though statements to this effect may be found in works of natural history, I cannot find one case which will bear investigation.”

In other words, says Darwin, animals and plants were not put on Earth solely for exploitation by humankind. This is not our kingdom. Again, nothing inherently anti-deity in this but in a way rather yogic — the universe unfolds as it unfolds. We can only select whatever characteristics a given species is born with — even if it pleases us, we cannot turn donkeys into singers.

In this chapter Darwin sounds passionate. He’s spent the past three chapters dissecting the domestication process, giving example after example of how humans select domestic animals, almost lulling the reader into a state of wonder at how clever we are when it comes to manipulating plants and animals. Then “Blammo!” We’re good, Darwin says, but Nature is better. Nature acts on unseen advantages, such as organs, senses, “on the whole machinery of life.” An unfortunate use of words, machinery echoes Descartes’ idea that non-human animals were machines, devoid of mind and consciousness. I’ll come back to this, but it does imply animals have no agency.

Darwin defends his use of the term Natural Selection: because metaphors are an important way to express ideas, it’s difficult not personifying nature. Yes, the “select” implies agency but “whoever objected to chemists speaking of the elective affinities of the various elements?” Darwin writes. Mercury is not an active element, to combine it with other elements takes effort. Does that mean mercury is lazy? Anti-social? Hydrogen combines with every element in the Periodic Table (except for the non-metal group). Does that make hydrogen promiscuous? If you’re a writer, yes, hydrogen hooks up with just about anybody — it’s effective to describe distinctly non-human objects or beings in human terms — readers understand ideas better that way. But the metaphors writers use influence readers’ thinking.

Darwin explains that Natural Selection refers to the “aggregate action and product of many natural laws” adding that more familiarity with his theory, means more acceptance of the terminology. But there’s a cogntiive dissonance here with what Darwin wants us to understand as Natural Selection and how he describes it. It’s a process with no thought behind it and yet is infinitely superior to what the the most “thoughtful” animal on the planet can do, plus, the words he uses to describe the selection of traits — “a good” mutation or “bad” mutation — or even to the phrase “the survival of the fittest,” implies life, whatever the life form, has value. Humans never accept machines as having the same value as life.

So let’s go back to Descartes and the idea of animals as complex organic machines. It leaves no room in Western thought for a world view that includes agency on the part of every life form in an ecosystem and recognizing that is actually key to a healthy ecological relationship when the top predator has enormous advantages (brain power.) Giving life forms agency might be a functional way to protect an ecosystem from overexploitation. Without the ability to assess and do something about, oh, say climate change, we may as well be just a supercolony of ants. (Maybe we really are.) By robbing other creatures of agency, a culture gives itself permission to take indefinitely.

Loch Ness Monster & Creationism

A Louisiana school uses the example of Nessie, the “elusive” monster in Loch Ness that draws tourists to the lake town of Inverness, as proof that humans and dinosaurs existed at the same time, poking a whole in Darwin’s evolutionary theory. How can they not understand that this is a long-running hoax?

To take a page from my book Hoaxed!:

Every now and then over the past 800 years, Scotland’s Loch Ness monster pops up and startles some unsuspecting passerby. So, pick a Nessie hoax, any hoax — a filmed Nessie, a photographed Nessie…how about a fossilized Nessie?

In 2000, Gerald McSorley was walking around Loch Ness when he accidentally tripped and fell into the lake, landing on a fossil. Was it Nessie? The fossil was turned over to the National Museum of Scotland where a paleontologist took a close look. The fossilized neck bones were embedded in limestone, a kind of rock not found in Loch Ness. And the fossil showed signs of being immersed in salt water, not fresh water. Plus, Loch Ness was formed about 15 000 years ago while the fossil, of a marine plesiosaur, was about 155 million years old.

The fossil wasn’t Nessie, it was probably planted there by a hoaxer. But Nessie lives on, if not in the lake, at least in peoples’ imaginations.

Hoaxed photo of the Loch Ness monster from 21 April 1934.

Yetis in Siberia….Seriously?

So much is wrong with this article….where to start? Synopsis: A Yeti footprint is found in an area of Siberia known for being a Yeti hotspot. (Can you spell t-o-u-r-i-s-m?) Apparently hairs were found and they are identical to hairs found in four different places around the world. Identical how? A “well-known” scientist with the latest equipment (which is…?) will release results in December about his analysis of purported Yeti remains from Switzerland. He has a plea on a website asking for more remains. It’s a hoax.

www.philippe-semeria.com

Scopes, May 25, 1925….Nurture or Nature?

Today is the day when a grand jury indicted Tennessee schoolteacher John T. Scopes for teaching Darwin’s theory of evolution by natural selection. Scopes violated a state law banning teaching a theory that does not include God’s hand in the existence of all life.

The teacher — a physics and math teacher — was only filling in as biology teacher. But he was young, 24, and when asked by the American Civil Liberties Union to “furnish the body for the defendant’s chair,” Scopes agreed.

Looking at the photo though, he was just 24?! This snippet from his memoir sums up why he was such a cool, progressive guy:

“I was born, a child of this strange century, on August 3, 1900, in Paducah, Kentucky, an Ohio River town that was a symbol of the live-and-let-live philosophy that I was taught at home.”

Climate Change and the Brown Argus Butterfly

Darwin wrote about species and their relationships with each other as a crucial part of natural selection. And new research shows the brown argus butterfly — pretty scarce in its habitat in the UK in the 1980s — has branched out, exploiting what was once a fickle relationship with other plants. In the past, the butterfly relied heavily on rockrose (Helianthemum nummarlium), a plant that grows on warm, sunny south-facing slopes (they’re beautiful in the garden since they bloom all summer.) 

But in the past 20 years warmer temperatures have made plants in another family, the Geraniaceae family, more favourable hosts for the butterfly’s eggs. Couple that with butterfly phenotypes that happily bypass rockrose to lay their eggs on dove’s foot cranesbill plants, and the fact that the butterflies are also probably escaping established enemies in the rockrose sites, and brown argus butterfly populations have moved 79 kilometres north in Great Britain.

[Brown argus butterfly, courtesy Louise Mair]

The de-evolution of British gallantry…

On a British ship, a woman is less likely to survive if it goes down — whether or not the captain gives a Women and Children First order.  A working paper investigating maritime disasters and comparative survival rates of women, men, and children revealed that if you’re a woman and you want to travel by boat, choose a non-British ship.

Researchers analyzed 18 maritime disasters spanning three centuries. Their other conclusions:  women’s survival rates have risen along with their status in society since the First World War, children fare poorly no matter what, and the duration of the disaster (a ship going down slowly allows social norms to dictate behaviour) has no association with social norms. When disaster strikes, the researchers write, it really is every man for himself.

To sleep: perchance to dream…or slow down rabies

The rabies virus evolves more quickly in bats that live in the tropics versus those that live in temperate zones. The difference? Sleep. Well, technically hibernation. Heat-loving bats have more opportunities to spread the virus since they’re active 24/7/12 (12 being months.) In temperate zones, bats hibernate for up to six months. That translates into fewer virus transmission, and reduced evolution.

Original study

Greek farmers arrive in Sweden, spread technology, genes, but what about the feta?

From DNA analysis of ancient burials in Sweden, scientists think they’ve clinched it: farming spread from southern Europe to northern Europe, via farmers migrating in and intermingling.

By teasing apart and comparing DNA from two burials less than 400 kilometres away, from two different cultures (one hunter/gatherer the other farmers), researchers concluded that sometime around 5,000 years ago, people from Greece or Cyprus mixed with the local Scandinavian populations. Their gift: farming and genes.

The scientists don’t know who to blame for rutabagas.

Ove Persson and Evy Persson at the Ajvide excavations in Gotland, Sweden.

Darwin & Relationships

Darwin Noticed:  “In Australia the imported hive-bee is rapidly exterminating the small, stingless native bee.”

Hats off to Darwin. Just when I think “Surely you could have cut to the chase Charles…” he sums up an idea with clarity and brevity. Maybe his affliction (he did have a loo installed in his study, something you don’t see in the postcards) provided the impetus for getting to the point.

Postcard of Darwin’s study at Down House

 Struggle for Life most severe between Individuals and Varieties of the same Species is the final bit of Chapter III. A good science writer uses examples so lay readers can draw a picture in their minds — hive-bee versus the solitary native bee. Darwin cites other invasive species that do far better in a novel environment than the indigenous species: rats, cockroaches, and swallows. “…but probably in no one case could we precisely say why one species has been victorious over another in the great battle of life,” Darwin writes.

Battle, victory, struggle; why did Darwin choose these words? Did word choice set the stage for evolutionary theory being so focused on competition that what he wrote in the follow up paragraph took a longer time to absorb into the collective psyche? Each form of life has a relationship with every other form of a life in a given habitat, Darwins writes, and we can’t predict those relationships.

Take an insect like the Red Imported Fire Ant (RIFA) from Brazil and set it loose in Alabama: the climate might be similar, but it will have different relationships with the novel life forms it encounters in a new habitat. We can never anticipate what the relationships will be. The idea is a big part of environmental education today. But who was reading Darwin in the late 19th century, anyone? Definitely not the guy who released European starlings in New York City in 1890.

“It is good thus to try in imagination to give to any one species an advantage of another,” Darwin writes. “Probably in no single instance should we know what to do. This ought to convince us of our ignorance on the mutual relations of all organic beings; a conviction as necessary, as it is difficult to acquire.”

So the “struggle for existence” could just as easily be the less catchy — “lucky advantages”

But, for Darwin, war it is. Thankfully, though, it’s painless compared with human war. I guess. “When we reflect on this struggle, we may console ourselves with the full belief, that the war of nature is not incessant, that no fear is felt, that death is generally prompt, and that the vigorous, the healthy, and the happy survive and multiply.”

A Population Checked: Competition, Climate & Predation

The garden at Down House

Darwin had the handy Parslow as butler, a cook, gardeners — servants of all kinds to keep Down House running. Still, it’s impressive how he used his own time. When you read The Origin of Species, and think of how you spend your own days, watching Downton Abbey or The Hour seems a shocking waste of time. “There must be some worms or weeds I can study!”

Following Darwin’s Malthusian-inspired musings on populations, he turns to what keeps a species in check. At different stages of life, some species are particularly vulnerable — as eggs, for example. Plants seeds, too, suffer enormously, mostly because they’re choked by the vegetation already on the ground. They have no hope with the competing growth. And this is where you think what would have happened had Darwin grown up with video games?

Ever curious, Darwin digs (or probably a gardener digs) a patch three feet by two feet to get rid of any competing vegetation and watches what happens. Each of the 357 weeds that come up, he identifies and marks, and waits to see what happens. Will they all live? Slugs and insects are the chief nemesis of 295 of the weeds.

Darwin also keeps a three feet by four feet patch of turf unmowed or not browsed by animals. Out of 20 plant species, nine species never make it.

Lest his readers start musing on the vulnerabilities of the young in obtaining food, and how food determines populations, Darwin reminds us that plants and animals are some species’ meal ticket. He’s setting the stage for the concept of a food web. Before that, he has to explain another factor: climate, which sometimes has a direct bearing on population: the bitter winter of 1884-5 destroyed four-fifths of the birds on his grounds. But hang on, says Darwin. “Climate brings on the most severe struggle between individuals, whether of the same or distinct species, which subsist on the same kind of food.”

So let’s say its a bad year for salmon because when juveniles headed to the ocean to get big and strong before migrating back to their natal streams, the climate was not in their favour. They had less food. Fewer salmon come back, which is bad for bears. Bad for humans too, but which species will ultimately get more salmon: humans or bears?