CHAPTER 9THE LADDER OF

CREATION

Jacob Bronowski The Ascent Of Man

English Gentlemen and Evolution+On the 27th December, 1831 Charles Darwin set sail for a 5 year round trip on the 2nd voyage of the HMS Beagle as the ship’s botanist, despite his father’s protest and the Captain, Robert Fitzroy’s dislike of his nose.

+Despite originally agreeing to go purely for an opportunity to collect beetles, the trip inspired him to take an interest in nature on the whole, and he spent most of his time exploring the geology and natural history of the places he visited, spending only 18 months at sea.+When he returned in 1836 he was convinced that different species diverge from a common source, but was not sure why they diverged.

•In 1838 he came upon his famous explanation for it when reading “for amusement” Thomas Malthus’ An Essay On The Principle Of Human Population. •Malthus said population multiplies faster than food and has to compete for resources.

However Darwin was reluctant to publish his new theory. It took him until 1842 to write a draft of The Origin Of Species.He stored it away with a deposit of money and instructions for his wife to publish it when he died.It took the work of Alfred Russell Wallace to encourage him…

Alfred Russell Wallace•Born in 1823 in Usk, Wales. He was 14 years younger than Darwin •Supported himself as a land surveyor for railway firms •This open air life inspired his interest in nature

+Whilst working at Leicester he befriended the better educated Henry Bates (known for work on mimicry between insects). +Henry taught him that there are thousands of varieties of each different species, with the example of beetles found in the Leicester area.

• Alfred began collecting different varieties of species in the Welsh countryside.

• As his interest grew he decided to become a professional naturalist at age 25.

• This led him to travel with Bates to South America in 1848 with £100 between them.

• He continued without Bates, but with local Indian guides up the Rio Negro (a tributary of the Amazon) in search of rare or undiscovered species that would make him rich.

• The river had flooded and the water allowed the canoe deeper into the forest.

• “The whole glory of these forests could only be seen by sailing gently in a balloon over the undulating flowery surface above: such a treat is perhaps reserved for a traveler of a future age.”

• Wallace was a keen observer of people as a part of nature, and recruited the help of the local Indians in his collecting of samples

• He was one of the first and few Victorian English to appreciate native tribal culture beyond dismissing them as ‘savages’

• He even wrote poetry praising their way of life “I’d be an Indian here, and live content to hunt and paddle my canoe”

• After conceiving the principle of natural selection he also believed that we were closer biologically as well.

• He spent 4 years in the Amazon before starting the trip home.

• On the way back he caught a fever. • Most of his captive animals died in the tropical rain • 3 weeks later his ship caught fire• All he recovered were some notebooks with his

observations, his watch and some shirts • “I…felt a kind of apathy about saving anything” • When he returned however he was convinced

common species diverge, but didn’t know how. • This didn’t discourage him in his profession though.• In 1854 he went to the Far East for 8 years,

collecting specimens in the Malay Archipelago.

Unlucky!

• By this time he was convinced species do diverge and was searching for how they did it.

• Published a paper On The Law Which has Regulated the Introduction of the New Species.

• In 1858 while sick with a fever on the spice islands he was inspired by Malthus’ essay.

• “The answer was clearly, on the whole the best fitted lived.”

Malthus was a Surrey born Economist who believed that as society grew it put more taxing limits on the environment to support it. Humans increase exponentially. Food increases arithmetically.

• Wallace knew Darwin was interested in the subject and sent him a copy of his idea, in 1858.

• Origin of Species 1859; became a best seller.

The Hornet 22nd March, 1871

•The living world was different now because it was seen to be a world in motion.•“The physical world ten million years ago was the same, and it’s laws the same…The living world is not the same…ten million years ago there were no humans to discuss it”

Louis Pasteur•French microbiologist born in 1822.•Created first rabies vaccine. •Invented methods to stop wine and milk souring - Pasteurization.

•In 1863 the Emperor of France asked him to look into problems in wine fermentation•He found bacteria could live without air.•This was crucial to understanding the beginnings of life, as the Earth would have been without it.

• Believed symmetry he observed in crystals would apply to organisms

• “The remarkable fact is that a chemical solution from living cells does just that.”

• He debunked the widely accepted myth of spontaneous generation, thereby setting the stage for modern biology and biochemistry. He demonstrated that organisms such as bacteria and fungi do not spontaneously appear in sterile, nutrient-rich media.

• Spontaneous generation, held that certain complex, living organisms are generated by decaying organic substances.

• He also described the scientific basis for fermentation, wine-making, and the brewing of beer.

The Building Blocks of Life• Stanley Miller created a simulation of what we believe the ‘primordial’ Earth’s environment was like.•He put an equivalent atmosphere in a glass and subjected it to effects similar to a violent early earth, such as boiling

The finding caught the imagination of scientists everywhere by suggesting that it might soon be possible to reconstruct the emergence of the first living cells from the soup of chemicals generated by natural conditions on the early earth.

• The Miller-Urey experiment which demonstrated that organic compounds can be created by fairly simple physical processes from inorganic substances.

• The experiment used water (H2O), methane (CH4), ammonia (NH3), and hydrogen

• The experiment tested Alexander Oparin's and J. B. S. Haldane's hypothesis that conditions on the primitive Earth favoured chemical reactions that synthesized organic compounds from inorganic precursors.

• Considered to be the classic experiment on the origin of life, it was conducted in 1952 and published in 1953 by Stanley Miller and Harold Urey at the University of Chicago

• Miller is considered a pioneer in the field of exobiology, which is the study of life beyond planet Earth.

• The chapter deals with Man’s understanding of life as a scientific process• Our most important discoveries took

place between 100 years of each other • The first; in the 1850s of evolution by

natural selection, discovered by Darwin and Wallace • The second, regarding the chemistry of

life.