Alfred Russel Wallace: Architect of Evolution

This progression, by minute steps, in various directions, but always checked and balanced by the necessary conditions, subject to which alone existence can be preserved, may, it is believed, be followed out so as to agree with all the phenomena presented by organized beings, their extinction and succession in past ages, and all the extraordinary modifications of form, instinct, and habits which they exhibit.

Wallace had discovered the Theory of Evolution. He sent his paper back to England, to establish his claim. By a supreme irony, Wallace addressed the paper to Charles Darwin, as he knew Darwin was interested in "the species question."

The Ice Ages were caused by astronomical cycles - another first for Wallace

What Wallace didn't know was that Darwin had independently read Malthus and had come to exactly the same conclusion. But Darwin had worked slowly and ponderously for 20 years. He was the tortoise who had now been overtaken by Wallace's hare.

Startled and confused, Darwin confided in the great geologist Charles Lyell. Ever the diplomat, Lyell presented both Wallace's paper and some of Darwin's preliminary results at the next meeting of the Linnaean Society in London.

It was Wallace's paper that prompted Darwin to publish his book, On the Origin of Species, within the next 18 months - a work that came to completely overshadow Wallace's original ideas on evolution.

Meanwhile, Wallace spent another four years in Indonesia, gradually travelling back westwards again. The explorer and his unprecedented collection sailed out of Singapore in 1862 for England. He didn't undertake any further exploration, but applied his mind to topics that ranged across all the sciences, from an astronomical explanation for the Ice Ages to a statistical analysis of smallpox outbreaks. He also refuted the idea that the 'canals' of Mars were built by intelligent Martians.

Wallace was eager to marry, but was shy with women. When one prospective wife turned him down, a botanist friend intervened and married the 43-year-old Wallace to his 18 year-old daughter. By all accounts it was a happy marriage.