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Athens is the only capital city in Europe where the air is more polluted outside than inside.

In AD 380, the Catholic Church issued a law specifically forbidding anyone to read the Bible whilst naked.

There is a plant called Hooker’s Lips (Psychotria Elata).

In 2006, later Republican presidential candidate Donald Trump said “If Ivanka weren’t my daughter, perhaps I’d be dating her.”

Since 1963, the reverse of the United States ten-dollar-bill has stated “In God we trust”. Between 2000 and 2017, the reverse of the Bank of England ten-pound-note has portrayed Charles Darwin.

See other: Quite Interesting Facts

On Indistinguishable Embryos

“No other explanation has ever been given of the marvellous fact that the embryos of a man, dog, seal, bat, reptile, etc., can at first hardly be distinguished from each other.”

– Charles Darwin

Eradicating Religion

‘One of the greatest challenges facing civilization in the twenty first century is for human beings to learn to speak about their deepest personal concerns—about ethics, spiritual experience, and the inevitability of human suffering—in ways that are not flagrantly irrational. We desperately need a public discourse that encourages critical thinking and intellectual honesty. Nothing stands in the way of this project more than the respect we accord religious faith.

I would be the first to admit that the prospects for eradicating religion in our time do not seem good. Still, the same could have been said about efforts to abolish slavery at the end of the eighteenth century. Anyone who spoke with confidence about eradicating slavery in the United States in the year 1775 surely appeared to be wasting his time, and wasting it dangerously.

The analogy is not perfect, but it is suggestive. If we ever do transcend our religious bewilderment, we will look back upon this period in human history with horror and amazement. How could it have been possible for people to believe such things in the twenty first century? How could it be that they allowed their societies to become so dangerously fragmented by empty notions about God and Paradise? The truth is, some of your most cherished beliefs are as embarrassing as those that sent the last slave ship sailing to America as late as 1859 (the same year that Darwin published The Origin of Species).’

Harris. S. 2006. Letter To A Christian Nation p. 28

Why did Agriculture Happen?

‘So why did agriculture happen? […]

Historians don’t know for sure, of course, because there are no written records. But, they love to make guesses. Maybe population pressure necessitated agriculture even though it was more work, or abundance gave people leisure to experiment with domestication, or planting originated as a fertility rite – or as some historians have argued – people needed to domesticate grains in order to produce more alcohol.

Charles Darwin, like most 19th century scientists, believed agriculture was an accident, saying, “a wild and unusually good variety of native plant might attract the attention of some wise old savage.”‘

– Green. J. (2012, January 26) The Agricultural Revolution: Crash Course World History #1

Evolution 101

‘Consider Darwin’s original phrase natural selection: everything from Cuckoo Birds that lay their eggs in the nest of other birds, to giraffes whose long necks are good for reaching food in high trees, to humans whose brains make up for their fragile bodies, are selected for, naturally.

An even better phrase would be non-random selection or maybe even non-random elimination. While all genetic mutations are generated by a random copying error or random variation completely beyond the animal’s control, the selection of those traits is not random.

Successful variations that allow you to survive and reproduce are determined by the very specific circumstances of your environment, where elimination – death – might not be far away.

So, the selection of your traits is done by a very specific and sometimes brutal list of criteria. This is why people who say that they don’t understand how all animals could have “evolved by chance” don’t really understand how evolution works.

Here’s another phrase that doesn’t get it right: “evolution is just a theory”. In everyday speech, theory means guess; but in science, a theory is something that was tested time and time again, explains many different observations and is backed up by a mountain of evidence.

Evolution is a theory like gravity is a theory, and you don’t go jumping out your window because gravity is “just a theory”.

Why are we so certain? Emily knows:

Evolution is one of the most tested, most utilised and most widely accepted theories in science. It’s backed up by literally tonnes of fossil evidence which can show us shared traits with species that no longer exist, and help us map out lines of descent for creatures that are around today.

DNA sequencing further tells us about lines of descent and you can measure the commonality of the DNA possessed by two animals to tell how closely related they are, and when they may have split off from a common ancestor.

Radiometric dating allows us to assign dates to various fossils, further helping us map out lines of descent.

Then there’s the simple fact that extinct species are always found in the same rock layers you’d expect to find them. Which is why you don’t see a bunny skeleton in Cambrian rock layers from half a billion years ago. That’s also how we know that Dimetrodon is not a dinosaur.

Closely related species are often geographically distributed near one another. That’s not to mention that we can see evolution happening before our very eyes: whether it be the discovery of a new species that recently moved into a different environment, the development of newly adapted bacteria into superbugs, the evolution of new breeds of rapidly reproducing insects, or the almost constant changes in gene distribution in animal populations all over the world.’

– Green. H., Graslie. E. (2014, October 29) The Evolutionary Epic: Crash Course Big History #5

Evolution by Natural Selection

‘The keystone of our story is evolution by natural selection. In the 1830s, a young Charles Darwin travelled around the world on the HMS Beagle – inarguably, by the way, the most important beagle of all time; I apologise Snoopy but it’s true. Darwin had the rare and amazing opportunity to study a great variety of the world’s wildlife, and upon returning to England he discovered that a variety of Finches he had collected on the Galapagos Islands had beaks that were suddenly adapted to their different environments and food sources.

Darwin later combined this idea with the observation of how populations tend to overbreed and strain their resources; I mean, if there is competition for resources in an environment, animals with useful traits would survive and pass those traits on to their offspring; those who didn’t survive long enough to reproduce would have their traits wiped out from the evolutionary tree: natural selection.

We talk about someone who does “good science” and Darwin was a good scientist; he worked on his idea for two decades, systematically finding new evidence to support his case; and then, finally in 1859 he published On The Origin Of Species and it sent shockwaves around the world. The book offered an explanation for why so many species that seemed perfectly adapted to their environment could have been formed by a blind but elegant law of nature. Darwin’s theory was so elegant yet so effective that his colleague Thomas Huxley exclaimed “How extremely stupid not to have thought of that!”

Sidenote: if you ever read On The Origin Of Species, try to get a first edition because in later editions, Darwin made a bunch of revisions in answer to some critics but he got it actually more right the first time.

Speaking of which, a bunch of the phrases only included in the later editions and commonly attributed to Darwin was “Survival of the fittest”, but that phrase was actually coined by Herbert Spencer, father of the more troubling Social Darwinism which tried to apply nature’s rather harsh laws to human social orders.’

– Green. J. (2014, October 29) The Evolutionary Epic: Crash Course Big History #5

Precambrian Supereon

In the geochronology of the Earth according to the Geologic Time Scale, the Precambrian supereon accounts for 88% of all geologic time. The Precambrian lasted from the Earth’s beginnings, over 4.5 billion years ago, until the start of the Phanerozoic eon, 541 million years ago. During these 4 billion years it covered the Hadean, Archean and Proterozoic eons.

Hadean eon (~4500–4000 million years ago)

The Hadean eon is the first subdivision of the Precambrian supereon and therefore the first geological eon. It began with the formation of the Earth around 4.5 billion years ago, and ended 500 million years later, 4 billion years ago.

The name “Hadean” comes from the Ancient Greek Ἅδης, the ancient Greek god of the underworld, in reference to the hellish conditions on Earth at the time: the planet had just formed and was still very hot due to high volcanism.

During this eon, the Earth was bombarded for millions of years on end with meteors from outer space. The valleys of craters left by this onslaught of rocks filled up and became the first oceans. Also, because of the heavy bombardment, pieces of rock broke away from the Earth and formed the basis of the Moon. The Hadean is also the eon in which it is suggested that life on Earth began.

“Far out in the uncharted backwaters of the unfashionable end of the western spiral arm of the Galaxy lies a small unregarded yellow sun. Orbiting this at a distance of roughly ninety-two million miles is an utterly insignificant little blue green planet whose ape-descended life forms are so amazingly primitive that they still think digital watches are a pretty neat idea.” – Douglas Adams, The Hitchhiker’s Guide to the Galaxy

Archean eon (4000–2500 million years ago)

The Archean eon lasted from from 4 billion years ago to 2.5 billion years ago. Although, in older literature, the Hadean is included as part of the Archean.

The name comes from the Ancient Greek Αρχή, meaning “beginning, origin” and is a reference to the fact that photosynthesis started to take place in this eon.

Even though it is suggested that life on Earth originated earlier during the Hadean eon, we known for certain that certain species of bacteria thrived during the Archean eon. It is also the eon during which the first continents were formed.

“Evolution did not end with us growing opposable thumbs. You do know that, right?” – Bill Hicks

Proterozoic eon (2500–541 million years ago)

The Proterozoic eon is the longest geological eon to date. It is the eon which precedes the Phanerozoic eon in which we currently find ourselves.

The name comes from the Ancient Greek and means “earlier life”. It represents the time just before the proliferation of complex life on Earth.

One of the most important events of the Proterozoic was the accumulation of oxygen in the Earth’s atmosphere. Also, the first appearance of advanced single-celled, eukaryotes and multi-cellular life, roughly coincides with the start of the accumulation of free oxygen. Finally, towards the end of the Proterozoic, the earliest arthropods, fungi and small shelly fauna appear.

“Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.” – Charles Darwin, The Origin of Species

See other: History of the Earth

Geologic Time Scale

When Aristotle (384-322 BC) observed that fossil seashells from rocks were similar to those he found on the beach, he concluded that those fossils were once living animals. He further deduced that the positions of land and sea had changed over time and thought these changes occurred over very long periods.

Of course, Aristotle was in no position to accurately determine the length of those long time periods. Nowadays however, thanks to radiometric dating (the measurement of decay in radioactive isotopes), we know that the Earth is approximately 4.54 billion years old.

“The geologist takes up the history of the earth at the point where the archaeologist leaves it, and carries it further back into remote antiquity.” – Bal Gangadhar Tilak, The Arctic Home in the Vedas

In order to accurately document the enormous history of the Earth, a system known as the Geologic Time Scale has been developed to divide the history of our planet into units. The Geologic Time Scale is made up of the following units of time:

  • Supereon (approximately 4 billion years)
  • Eon (half a billion years or more)
  • Era (several hundred million years)
  • Period (between tens and one hundred million years)
  • Epoch (tens of millions of years)
  • Age (millions of years)

Because each unit of time summarizes the major events and characteristics of a certain geological time span, there are no fixed time frames for the different units of time.

“Geology gave us the immensity of time and taught us how little of it our own species has occupied.” – Stephen Jay Gould, Ever Since Darwin: Reflections on Natural History

See other: History of the Earth