Human-Time Speciation

Just a regular Culex pipiens mosquito.

We all know that random mutations and artificial selection is the mechanism that leads to that advent of new species. The problem is, it's so darn hard to observe in the wild because of how long it usually takes. This is a process that can take tens of thousands of years.

(Note: The definition of "species" I'm going with is a set of animals that can breed together and produce fertile offspring.)

However, it doesn't always have to take that long. Bill Nye wrote about a species that evolved over the course of what could be a human lifetime: a new form of mosquito.

This new species came into being as an isolated population of regular, ol' mosquitoes that made it into the London Underground. Of course, mosquitoes have lived on the British Isles for ages. But, scientists suspect that during the London Blitz of World War II, when citizens would seek refuge underground, mosquitoes followed them down and were capable of establishing a colony by breeding in the standing water that formed near the tracks.

With this steady supply of human blood and puddles for their eggs, these mosquitoes saw no reason to reemerge from underground. As a result, they stopped interbreeding with their above-ground counterparts.

Now, this is where the evolution takes place. Over time, the two groups began to change their habits. In the climate-controlled Tube, the underground mosquitoes dropped their ability to hibernate during the winter months. They reconfigured themselves to feed exclusively on mammals, mostly humans. Also, they gained the ability to breed in confined spaces, which the above-grounders can't do.

Physiologically, the two species are very similar. I guess only about fifty years isn't enough time to produce any really neat external changes in mosquitoes. However, over the course of those fifty years, the two have drifted genetically enough to the point where it's very hard for the two of them to mate successfully together.

Most of the time, the two groups cannot produce eggs at all. Sometimes, they'll produce eggs; but, that new generation is infertile (the mules of the mosquito world). While it's is probably open to interpretation, this seems close enough for me (a nobody on the internet) to declare them separate species.

Sources:
"Undeniable: Evolution and the Science of Creation" – Bill Nye
"Culex pipiens in London Underground tunnels: differentiation between surface and subterranean populations" – Katharine Byrne and Richard A. Nichols (Heredity 82, 1999)

L.A.S.E.R.

U.S. Army Research Laboratory, 2013

For those who don't know, "laser" is an abbreviation for light amplification by stimulated emission of radiation. That really does sum things up nicely, but a little more explanation might be in order.

First of all, whenever an atom drops from a high energy state to a lower, the atom emits a photon of energy equal to the difference in energy states. This type of thing occurs spontaneously in nature all the time, but a laser works by forcing this kind of reaction.

To stimulate this photon emission, the gas inside the laser cavity is energized from an external source, such as an electrical current from a battery. For example, a mixture of helium and neon gets zapped, which causes the atoms to move around rapidly. The idea is that the twitchy helium atoms would bump into the neon atoms and cause them to jump to a high-energy state. Within moments, one of the neon atoms will naturally drop to a lower state and emit a photon.

When one of these photons bumps into another energized atom, it somewhat counter-intuitively causes the atom to drop to a lower energy level (the book uses the term "sympathetic vibration", but I'm not too clear on how that works right now) and release a photon with the exact same properties as the one that struck it; one photon becomes two. These reactions snowball into more photon emissions as the new photons react with other energized atoms. In a very short time, a lot of photons are bouncing around with the exact same properties as all the others.

All of this is occurring within a cylinder with carefully aligned mirrors on each end. The photons bounce back and forth between these mirrors until they gradually line up and fit through the hole at one of the ends, all at the same wavelength (colour), moving in parallel, and in the same direction. Voilà! A laser beam.

"Physics for the Rest of Us" - Roger S. Jones

Ye Olde C-Sections

As it turns out, the caesarean section isn't as modern as I thought it was. For some reason, I assumed it was a 20^th century invention. In England, as it turns out, this surgery was a thing since at least the 1770's. It's likely Europeans had been carving out babies since even earlier. Though, back then, this operation was always a last resort sort of thing.

Childbirth in the 18^th century was much riskier than today's ultra sterile birthing facilities. Generally, the whole thing involved only the mother and some female family and friends. Occasionally, a paid midwife would be brought in. These midwives had no formal qualifications, just a lot of experience birthing babies.

Formally-trained male midwives were a relative rarity. However, they knew what they were doing. They had the research knowledge, experience, and fancy forceps to get things done right.

Either way, there were no anaesthetics or antibiotics. Mothers-to-be just had to grin (or grimace) and bear it. This was further exacerbated when birthing complications necessitated a caesarean.

William Cooper, in 1774, was the first doctor to perform a caesarean in England where the baby lived. However, the mother did not survive. It should be noted that surgical pain and a lack of anaesthetics usually results in dead bodies.

In 1793, James Barlow performed the first c-section where the mother survived. In this case, however, the baby did not survive.

It wasn't until around 1819 that the first recorded successful c-section, for both parties, was performed in the British Empire. In this case, it was performed in South Africa by an educated female midwife posing as a man.

Childbirth remained difficult and deadly for decades. Before 1800, about 1.5% of women died in childbirth. Compare that to about 0.0082% in 2010. (Note: the book that gives the former figure does not clarify if it was 1.5% of childbirths resulted in death or 1.5% of all womanly deaths were from childbirth)

Sources:
"Jane Austen's England" - Roy and Lesley Adkins
"Maternal mortality: how many women die in childbirth in your country?" - Simon Rogers
"Cesarean Section - A Brief History" - Jane Eliot Sewell, Ph.D.