Search Results

This chapter examines how tree-like representations took on new meanings as an understanding of genetics and the importance of population-based studies emerged. Before Charles Darwin's On the Origin of Species was published in 1859, evolutionary trees of life were a novelty. After Darwin, they became a necessity, thanks to the foundations that he laid for “descent with modification by means of natural selection.” With the turn of the twentieth century, American scientists began to engage in the production and dissemination of phylogenetic trees. The science of paleontology began ascending in stature in the United States, especially in East Coast institutions. This chapter looks at some of the scientists who produced a variety of evolutionary trees guided by Darwin's precepts, particularly Ernst Haeckel. It also considers the trees produced by Max Fürbinger and the decline in audience interest in visual representations of trees.

This chapter examines how scientific interest in Charles Darwin's evolutionary trees declined and then increased in the twentieth century. As the nineteenth century drew to a close, the reality of evolution became firmly established among scientists. Darwin deserves credit for the overused idea of a paradigm shift—evolution was a scientific “fact,” but not so for his theory of natural selection. Intellectual retreat from Darwin's natural selection can be attributed in part to his failure to provide an adequate hypothesis of inheritance or the source of variation on which his natural selection was to act. This chapter explores how the still emerging field of vertebrate paleontology and the ideas of evolutionary mechanisms that accompanied them affected visual representations of evolution in trees. In particular, it looks at the so-called bone wars between Edward Drinker Cope and Othniel Charles Marsh in the United States, Henry Fairfield Osborn's aristogenetic trees, and the rise of neocreationism. It also considers the contributions of William King Gregory, Alfred Sherwood Romer, and George Gaylord Simpson in visualizing biological order.

This chapter examines Charles Darwin's various evolutionary trees, which deal more with his attempts to understand the process of evolution than its pattern. The idea of “descent with modification,” or simply evolution, was a hotly debated topic by the early nineteenth century. The debate lacked what Darwin provided, along with Alfred Russel Wallace: a mechanism, and the mechanism was natural selection. After the publication of Darwin's On the Origin of Species in 1859, no one would ever look at a tree of life in the same way. This chapter looks at Darwin's tree sketches done during the 1840s and 1850s, as well as his “Big Book” that deals with evolution by means of natural selection. It also analyzes a pair of Darwin's trees with competing views on the origin of placental and marsupial mammals and another tree that reflects how Darwin saw man's place in nature.

This chapter examines how perceptions of our place in nature evolved over time as we discovered and attempted to understand the vast living and nonliving world that surrounds and defines us. How the vast majority of people view humans' place in nature, even when accepting that evolution occurred, can be summed up by a quotation in William Shakespeare's Hamlet: “What a piece of work is a man! How noble in reason, how infinite in faculty! In form and moving how express and admirable! In action how like an Angel! In apprehension how like a god! The beauty of the world! The paragon of animals!” This chapter looks back at the earliest tree-like attempts to visualize supposed racial differences as well as the ancestry of all living humans and proceeds by discussing Charles Darwin's evolutionary trees and the question of when humans departed Africa as well as its implication for the meaning of the human race. It concludes that evolution has not produced a clearcut phylogeny of humans or any group of plants or animals that would result in a neatly branching family tree.