Lecture 1: The age of the Earth & fossil record 1500-1830 (Part 1) Evolution: - Change in biology, change of living things overtime (Image of ape transforming to human is NOT evolution!) - Evolution is not a law of nature/ force of nature like gravity Creation stories of the world - Thousands of different tribes, ethnic groups, people around the world had different creation stories that explains the world they live in Ancient Egyptians (c. 2700 BCE) - Gods created the world out of a lifeless sea of chaos Believed that after death, a person’s soul faced judgment. If heart weighs more than a feather, person would be sent to a place of punishment Norse / Viking - World was created by gods from body of a dead giant (c. 500 BCE) Batak of Sumatra - Sky goddess came down to the sea and a handful of earth/soil was dropped down to give a place to live on (Sumatra) Trapped in a metal box underneath the island was a dragon that sometimes rolls around in its box, explaining why the island was frequently torn with earthquakes Australian aborigines - First humans were regurgitated by a great rainbow serpent in the sky Mayans of Central America - The creator gods made humans out of maize/corn (maize was their main food) (they thought you are what you eat xDDD) Inuits/Eskimos - Aurora borealis / northern lights are the dancing souls of their ancestors in the sky Animal creation stories Goose barnacles - Barnacle goose Barnacle goose do not nest in Europe, no one ever seen a barnacle goose nest/egg/chick, just appeared out of nowhere Thought barnacle goose grew out of the sea creatures Thought eagle dives into the sea dies and comes out of the water reborn During Middle Ages, thought hedgehogs walked into strawberry patch, rolled around on strawberries to stick on their spines, and went back to their burrow to eat their strawberries Mandrake root (looks like human) that’s why they have spines Legend has it that if you pull it out and hear it screaming you will die Solution: tie rope around dog and around the root, stuff ears with wax/cotton, kick the dog and it will pull out the root without killing you Creation stories of ancient Hebrews (c. 540-330 BCE) God up in heaven, Garden of Eden on earth, stars and planets around earth, outside that is a body of water, explaining why sky is blue James Ussher (1650s) - - Archbishop in Ireland Wanted to estimate the age of the Earth using the Bible and other ancient documents Many textbooks and websites mention him as if he was an idiot Prof: “We shouldn’t judge them based on standards of our own times, no one in the past will live up to our standards and values. The past is a different world, people thought very differently from us.” Came out with an estimation of Earth being 6000 years old (created in 4004BC) His idea became popular, many Christians in Europe thought this is what the Bible said, but this estimate made its way into the Bible 19th century Bible (1800s) - Annotation from Bible shows 4004BC Things not mentioned in creation stories – like fossils Ancient Greeks and Romans Hesione vase (c. 550 BC) - Shooting arrows at monster, monster looks like skull of extinct elephant. They think the large bones and remains are that of giants and monsters from their mythology - Skull of elephant with a cavity infront - In Yorkshire, an abbey was founded by Saint Hilda. Full of ammonites / snake stones Local legend was that when St Hilda founded the place, she found that it was full of snakes. She took her staff, struck the ground and all the snakes miraculously turned to stones. Carved by local craftsmen to make ammonites look more like snake Nicolas Steno (1667) - Danish Bishop When he was in Italy, a giant shark was caught by local fisherman, and he investigated it Every tiny detail of shark’s teeth were same as tongue stones, he argued that why tongue stones look just like shark teeth is because THEY ARE shark teeth, which had turned to stone But how did they get in the rocks? - - Sharks live in water When they die their teeth fall into the mud Large parts of seas and lakes where sediments were gradually washed off from shore due to rain and falls down as silt or mud, building up layers based on the law of original horizontality and law of superposition Many ports and harbour of ancient Greeks and Romans are gone, they are completely filled up with silt Leonardo da Vinci - Noticed that fossils are not randomly scattered as if by a great flood But rather they were grouped together, like with like, as if they were from the same habitat Invention of the Microscope (1600s) - Suddenly able to see little things that were previously too small to be seen with naked eye Robert Hooke published Micrographia in 1665 People were filthy in the past, everyone had fleas on them all the time People were shocked when Hooke published the image - Fossils originally meant “dug up thing”, did not have connection to a previously living thing (that was a later idea) Fossils could be a crystal, or an interestingly shaped rock - He had a piece of fossilised wood, and saw little chambers He then looked at different types of living woods, and found one that has little chambers with exact same shape and orientation. Realised he had somehow found a piece of wood that turned into stone (fossil). - He gave the little chambers in living things a name, “Cells”. Originated from monks living in monasteries, their living spaces were like a prison. Monk’s bedroom in a monastery is called a “Cell”. We also use that word today for a prison cell, with small identical bedrooms. John Ray (1627-1705) - English naturalist Published a book “The Wisdom of God manifested in the Works of the Creation (1691)” (means the wisdom of God seen through nature) Tried to catalogue the all species of animals and found out there were thousands of species Speculated that the way animals were expertly adapted to their way of life prove that they have been designed by God Believed that the number of species in nature is fixed and limited since the beginning, meaning no new species have been created Carl Linnaeus (1707-1778) - - - - Swedish naturalist Became a cataloguer/ taxonomist By this time, there were >2x the number of mammals known from Ray’s time Species are clear cut and distinct The only source for a living thing is from parents of the same species i.e. living things don’t spontaneously spring into life from nothing, it was a common widespread belief back then (Spontaneous generation: eg. Dropped meat on the ground and came back discovering it’s full of maggots eating it, people would say the maggots just appeared in the meat) Linnaeus was against the spontaneous generation theory There were far too many species in the world to fit in Noah’s ark (seemed like an irreligious thing to say when he was a devout Christian) è Christians back in the day were not devoted to a literal reading of the stories in the Bible! People today are surprised how could these religious men say stories from the Bible aren’t true, but the fact is that they did. (Prof: try to think just like the person you are who lives today, but also try to grasp the fact that ppl in different times lived differently. Just like ppl in diff places think differently, with diff traditions and beliefs. Linnaeus introduced a binomial nomenclature, two Latin names: genus and species Eg. Homo sapiens (Linnaeus named us that!) Homo = man, sapiens = thinking Before him, naturalists would give long paragraph descriptions of species as their official name Genus is the group, species is the specific name. 4400 species of animals and 7700 species of plants For him, the fact that all plants and animals were classifiable according to the system proved that there was divine design i.e. God must have designed the natural world Declared that there is no extinction - Paradoxa – crazy creatures such as mermaids, unicorns è Back in the days there were many reports that travellers seen mermaids but it couldn’t be proven. He made this category in case they turned out to be true. - Hierarchical system of classification What is a species? Javan myna (Acridotheres javanicus), a common species of bird in SG Common Myna Common Hill Myna Georges Buffon (1707-1788) - Frenchman Also wanted to find out the age of the Earth, but using an experimental way unlike James Ussher who used books Speculated that Earth started as a glowing molten sphere that gradually cooled He had an iron foundry, and made iron spheres of diff sizes, heated them up and measured rates which they cooled The Epochs of Nature / Les Époques de la nature (1778) Estimated Earth as 75,000 years old - - Observed that species in different parts of the world (like America vs. Europe) are so different that they must have been created separately there Speculated that species can change a little to fit their environments, but not into other species. (Europeans have been settling in different parts of the world, taking their livestock with them. Recognised that the livestock were a little different from the ones back home) Modern mining became quite sophisticated by this time, the deeper you drill down into the Earth, the hotter it gets Miners started realising the rocks were going down in Earth at an angle - From the diagram, digging straight down, we encounter a dark coloured rock followed by a light coloured one, and back to dark coloured again at the deepest point Dawn of the study of Geology - - James Hutton (1726-1797) - - - Scottish geologist Hutton’s Theory of the Earth (1795) Cliff made out of sedimentary rocks (going back to Nicolas Steno), rock layers build up horizontally But he found out that the layers who used to be horizontal were now vertical He pointed out that each layer would take thousands of years to form, and there are so many of them + the time taken for them to become vertical + time taken for them to moved up into the air to be eroded and move back down again He said what we see here is the evidence from the Earth itself of an age that is unimaginable by the mind of Man Believed that Earth was essentially infinite, that it was so unbelievably ancient that it basically existed forever - BUT, if dry land is always being washed away into the sea (erosion), eventually there wouldn’t be land left on Earth Hutton thought that God wouldn’t allow simply Earth to be washed away, so he theorised that if forces of erosion wash Earth away, there must be forces that counteract and create new Earth, maintaining a balance (Eg. Earthquakes and volcanoes), forming a circular/cyclical system that goes on forever (Prof: impt lesson to takeaway is that these early geologists were all religious men, many of them were clergy/ priest. They were the same ppl that discovered that Earth was not thousands of years old. Contradicting a literal reading from the Bible wasn’t that crucial in those days, it wasn’t a deal breaker for most ppl. Ppl could accommodate these scientific ideas with their existing religion) William Smith (1769-1839) - Worked for companies digging canals, before invention of railways Companies started digging industrial network of canals Expert surveys had to be done when digging due to uneven landscape while the canal had to be levelled - He found out that the same fossils were always found in the same layer (strata) of rocks The order of the beds of rocks is the same everywhere those rocks are found Lower layer of rock is older, and the one above it is newer. With lots of layers, we get to know the history of that part of the world Means that fossils of lower beds are older than the ones above it. è Became possible to reconstruct the history of life based on actual remains rather than traditional stories - - First geological map in the world (1815)
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