Widely regarded as one of the most influential personalities in the history of mankind, Charles Darwin was an English biologist, naturalist, and geologist. He is credited with publishing the Theory of Evolution, which explains the evolution of life from a unicellular organism to human beings. A prolific writer, Charles Darwin also wrote important books on plants and barnacles.
Henry David Thoreau was an American philosopher, essayist, poet, and naturalist. He is credited with popularizing transcendentalism and simple living. His philosophy of civil disobedience, which was detailed in his essay of the same name, later influenced world-renowned personalities like Leo Tolstoy, Martin Luther King Jr., and Mahatma Gandhi.
American–Australian naturalist Terri Irwin is best known as the co-host of The Crocodile Hunter, along with her husband, the late animal expert Steve Irwin. She has also been part of shows such as Croc Files and Crikey! It's the Irwins, and helped in the development of Australia Zoo.
Pliny the Elder was a Roman natural philosopher, author, and army and naval commander of the Roman Empire. His work Naturalis Historia became an editorial model for the present-day encyclopedias. Today, his statue greets the visitors of Cathedral of S. Maria Maggiore in his hometown, Como.

Bob Irwin, better known to the world as the father of legendary Australian conservationist Steve Irwin, is a conservationist in his own right. Initially a plumber, he later built the Beerwah Reptile Park, which later became Australia Zoo. Following Steve’s death, he cut all ties with the zoo.
As a child, Alexander von Humboldt was sickly and a bad student. After failing to shine in economics and engineering, he grew up to revolutionize the domain of geography. He is remembered for his research on magnetic storms and his treatise on nature, Kosmos. He also spoke about climate change.
French biologist Jean-Baptiste Lamarck acquired his love for plants while serving as a soldier in the French army. Following an injury, he quit his military career but retained his love for botany. He later taught zoology, studied the classification of invertebrates, and also coined the term biology.
Ernst Haeckel had initially practiced medicine before he gained an interest in Charles Darwin’s theory and began exploring zoology and related fields. He not only coined terms such as ecology, but also named numerous species and created a genealogical tree. He drew numerous figures of animals and sea creatures, too.
British naturalist Joseph Banks is remembered for accompanying Captain James Cook on his voyage across places such as Brazil and Tahiti. He had also been the president of the Royal Society for over 40 years. Both his herbarium and library now find a place at the British Museum.

Best known for her iconic book Born Free, which describes her experiences of raising a lion cub named Elsa, Joy Adamson was a noted Austro-Hungarian wildlife conservationist. She excelled in music and medicine in her younger days and later settled in Kenya with her third husband, conservationist George Adamson.
Georges Cuvier was a French zoologist and naturalist. A major figure in the early 19th century's research of natural sciences, Cuvier played an important role in establishing the fields of comparative paleontology and anatomy by comparing fossils with living animals, for which he is sometimes regarded as the founding father of paleontology.
Two-time BAFTA-winning naturalist and explorer Steve Backshall soared to fame with the BBC program Deadly 60. He has also worked with the Discovery Channel and the National Geographic Channel. He has written The Falcon Chronicles, a series of children’s novels, among other books, and loves mountaineering and martial arts.

A pioneer of physical anthropology, Johann Friedrich Blumenbach laid down one of the first racial classification systems for humans after studying human skulls, dividing mankind into five racial groups. Born into a family of academics, he was a prodigy. He was against scientific racism, though his theory promoted the degenerative hypothesis.

German-born Dutch naturalist and artist Maria Sibylla Merian is remembered for her drawings of insects and plants. She also contributed to the development of entomology through her detailed work on insects and her documentation of a butterfly’s metamorphosis. Metamorphosis Insectorum Surinamensium is her best-known work.

British doctor Hans Sloane traveled to Jamaica as a personal physician of the 2nd duke of Albermarle and was soon engrossed in the natural species of the region. He documented his collections, and they eventually helped form the British Museum. He is also known as the inventor of drinking chocolate.

Georges-Louis Leclerc, Comte de Buffon was a French mathematician, encyclopédiste, cosmologist, and naturalist. He is best known for authoring and publishing Histoire Naturelle, an encyclopaedic collection of 36 volumes, which he worked on for 50 years. His work had a strong influence on two subsequent generations of naturalists, including popular French scientists like Georges Cuvier and Jean-Baptiste Lamarck.


Born to a poor fur dealer, Conrad Gessner was sent to study under an uncle who dealt in medicinal herbs. He then studied theology but later grew up to become a Renaissance polymath, excelling in subjects such as natural history and medicine. His Bibliotheca universalis remains a major work in bibliography.



American marine biologist, ornithologist, and entomologist William Beebe is remembered for his exploratory expeditions conducted for the New York Zoological Society. He also co-discovered the Bathysphere, penned many books, was a renowned lecturer, worked with the New York Zoological Gardens, and led tropical research at the New York Zoological Society.


English nun Mary Ward was one of the first to show how influential women could be in the Church. Her work led to the development of the Congregation of Jesus and Blessed Virgin Mary, or the Loreto Sisters. She traveled on foot all across Europe, establishing schools and was often criticized by traditionalists.

Irish-American theologian John Dominic Crossan, who has previously been a Roman Catholic priest, was also associated with the Jesus Seminar. It is believed, he had quit Catholic priesthood to marry Margaret, his professor wife, and had then focused on teaching and writing. His written works include Who Killed Jesus?

Roy Chapman Andrews was an American adventurer, explorer, and naturalist. He is best remembered for his association with the American Museum of Natural History where he also served as the director. Andrews is credited with bringing to the museum the first-known fossil dinosaur eggs. His life and career are said to have inspired George Lucas' famous character, Indiana Jones.

British banker John Lubbock, 1st Baron Avebury, better known as Sir John Lubbock, had also been an MP. However, he is best known for his contribution to ethnography and archaeology. He is also credited with coining the terms Paleolithic and Neolithic, and is known for his books on animal behavior.

Eduard Schnitzer, or Emin Pasha, was born into a German Jewish family in modern-day Poland. A qualified physician, he moved to Constantinople after being disqualified in Germany. He not only served the Ottoman rulers but also surveyed and explored Africa extensively. He was eventually killed by Arab slave raiders.



German naturalist Peter Simon Pallas was born to a professor of surgery and had, by age 15, formulated classifications of several animal groups. He chiefly worked in and around Russia, and is remembered for his 3-volume geological study, Journey Through Various Provinces of the Russian Empire.

British-Argentine author, naturalist, and ornithologist William Henry Hudson not just published a number of ornithological studies but also several novels, such as Green Mansions. He criticized Darwinism and was inspired by Samuel Butler’s writings. He was also part of the Royal Society for the Protection of Birds.

French naturalist Étienne Geoffroy Saint-Hilaire is best remembered for his principle of unity of composition. He also laid down the idea of teratology, or the study of animal abnormalities. He was also part of Napoleon’s scientific expedition in Egypt and later taught zoology at the University of Paris.



Chinese pharmacologist and scholar of the Ming dynasty Li Shizhen is remembered for his elaborate compilation Compendium of Materia Medica, which offered descriptions of over 1,000 drugs and provided instructions for about 11,000 prescriptions. His book was a benchmark in Chinese medicine and was translated into several languages.



Seventeenth-century German physician and traveler Engelbert Kaempfer had been on trade missions across the world, including places such as Russia, Iran, Java, and Japan. His written experiences about his stay in Japan became a valuable source of information on the flora and fauna of the country.

Dutch naturalist Jan Swammerdam was the first to detect red blood cells. Though a qualified doctor, he never practiced medicine, and took to research instead. Known for his research on anatomy, he also revolutionized the study of insects, proving that the egg, larva, pupa, and adult are all the same organism.




French naturalist Bernard Germain de Lacépède is best known for his contribution to fellow French naturalist Comte de Buffon's Histoire Naturelle. He enriched the world’s knowledge of fishes and reptiles. Following the rise of Napoleon, Lacépède joined the French Senate and later became a minister of Bourbon state.

José Bonifácio de Andrada was a Brazilian statesman. He was also a naturalist, mineralist, and professor. He was a significant proponent of Brazilian independence and also spearheaded the abolition project in Brazil. He was of the opinion that a new national capital should be created in Brazil's underdeveloped interior. As a naturalist, he discovered four new minerals.

German naturalist and botanist Lorenz Oken is remembered as one of the most significant German natural philosophers of the 19th century and a leader of the Naturphilosophie movement. His studies on Wolfgang von Goethe’s theory on the vertebrate skull helped prepare ground for Charles Darwin’s theory of evolution.

