Alfred Russel Wallace

In 1866, he married Annie Mitten, daughter of William Mitten, an expert on mosses. They were blessed with three children: Herbert, Violet and William.

In subsequent years, he made some bad investments in railways and mines which resulted in a financial crisis for him and his family. It was only after the efforts of his friends, especially Darwin, that he was awarded a £200 annual pension in 1881, which stabilized his financial condition.

He died on November 7, 1913 at his home in Broadstone, Dorset, England, at the age of 90. He was buried in the small cemetery at Broadstone, Dorset.

He was born on January 8, 1823 in Kensington Cottage near Usk, Monmouthshire, England, to Thomas Vere Wallace and Mary Ann Wallace. He was one among the nine children of his parents.

In 1828, his family moved to Hertford where he received his early education from the Hertford Grammar School for the next six years.

His father inherited some income-generating property but he wasted most of it on a series of poor business decisions. Alfred was ultimately forced to leave school in 1836 as a result of deteriorating financial condition of his family.

He was sent to London to work with his older brother, John, an apprentice builder. While in London, he attended lectures and read books at the London Mechanics Institute, working on his self-education.

In 1837, he went to work as an apprentice for his eldest brother, William. Their business eventually settled at Neath in Glamorgan in Wales in 1839–40 but after few years, due to harsh economic conditions, the business weakened and Alfred left the job at his brother’s firm.

Later, he found a teaching work at the Collegiate School in Leicester. While working as a teacher, he met an entomologist, Henry Walter Bates, who persuaded him to collect insects for research purposes. In 1845, William died and he resigned from his teaching job to assume control of his brother's firm along with his brother, John.

The business eventually failed and he found work at a firm as a civil engineer. His work mostly involved spending a lot of time in the countryside which permitted him to collect insects, his newly formed passion.

Along with his brother John, he started his own architecture firm and worked on several projects including the Neath Mechanics' Institute, founded in 1843. He was persuaded by the founder of institute to deliver lectures on science and engineering in the institute.

In 1848, he and Bates started their journey to Brazil in search of insects and other animal specimens in the Amazon rainforest. Their plan was to bring them to United Kingdom and sell them to collectors.

His most prominent work was conceiving the ‘theory of evolution through natural selection’. It is one of the most celebrated works in the history of evolution.

He also performed pioneering works in biogeography and became a leading expert on the geographical distribution of animal species.

‘The Malay Archipelago’, an account of his studies and adventures, published in 1869, became one of the most popular books of scientific exploration of the 19th century.

One of his notable works was the ‘Wallace Effect’, a hypothesis on how natural selection could contribute to speciation by encouraging the development of barriers against hybridization.