Letters to a Young Scientist

Chapter 12 begins with an illustration of “the most primitive known living ant” (133).

Wilson and Brown attempted to find the species of dacetine ant most similar to the common ancestor of all dacetine ants. Wilson thought of it as his “personal grail.” He found the ant in Suriname and learned a lot about its behavior and diet. Later, he pursued another “grail” when he searched for a once-common but now rare species of ant in Sri Lanka. After several false starts, he managed to find living colonies of the species.

Although these successes were significant, Wilson really wanted to find the closest living equivalent to the ancestor of all ants. He hoped to find an ant that did not live in a colony so that he could study how ants’ complex social structures first came into existence. One such species was rumored to live in Australia, so Wilson and some colleagues tried hard to locate it. They were unsuccessful, which was a major disappointment. Other scientists located the ant on a later expedition, only to find that these ants were also social and formed colonies.

Wilson found it very frustrating not to be able to determine how ants originally evolved. Then, in 1966, new fossilized ants were discovered dating back 90 million years. These ants had some traits that resembled wasps, demonstrating the gradual divergence of species that would one day become modern ants and wasps. Other fossil discoveries provided insight into ants’ physiology dating back up to 150 million years, but of course these discoveries said nothing about those ants’ social behaviors. In 2009, researchers found an ant in the Amazon that looked radically different from any known species, expanding scientists’ understanding of ant diversity.

Wilson ends this series of anecdotes by noting that while his work might not seem important to most people, it is “at a different level from an equally impassioned devotion to, say, fly fishing, Civil War battlegrounds, or Roman coins” because it represents a “permanent addition to knowledge of the real world” (148).

This chapter begins with a diagram of part of the tree of life that shows genetic exchange among bacteria, eukaryotes, and archaea. 

In 2003, although he had technically retired and stopped accepting new PhD students, Wilson made an exception for a particularly promising applicant called Corrie Saux (now Corrie Saux Moreau). She was especially enthusiastic about ants, with “tattoos of ants on her body to prove it” (152). For her PhD, Moreau took on the ambitious task of using DNA sequencing to create a portion of the ant family tree. When the project fell through, she became even more ambitious, electing to create the entire family tree. Wilson was so impressed by her dedication and ambition that he agreed to help her secure funding for herself and for a research assistant.

Just as she was about to complete her work, Moreau learned that another group of scientists had just done the exact same project as her. Fortunately, their family tree matched up with hers, bolstering the work of all researchers. Wilson uses Moreau as the ideal example of a young scientist. Any new researchers hoping to succeed should aim to emulate her skills and temperament.

The chapter opens with a map that shows the locations of cichlid fish habitats across Africa.

Wilson strongly encourages young scientists to ensure that they have a thorough knowledge of their desired field of study. Great discoveries require a lot of background knowledge, or else they might be misinterpreted or easily missed. To illustrate this point, Wilson describes the scientific backgrounds of Steven Weinberg, a theoretical physicist, and James D. Watson, one of the researchers who helped discover the double helix structure of DNA. Both of them, like all reputable scientists, spent many years learning as much as possible about their fields. Wilson relied on his own expertise when, between 1985 and 2003, he attempted to classify all of the species in the ant genus Pheidole. This was challenging, as Pheidole is a larger genus than almost any other. Taxonomy work on the genus had so far been scattered and was woefully incomplete. 

Initially, Wilson worked with his former mentor, Brown, on the project. When Brown died in 1997, Wilson continued alone. When Wilson finally published the book, it described 624 species of ant in total, 334 of which had never been described before. Even that enormous effort did not include every ant in the genus. During his research, Wilson tried introducing fire ants to a nest of Pheidole ants to test their behavior. He learned that the Pheidole ants would rip a fire ant apart, because if a single fire ant were to alert its colony to the presence of Pheidole ants, the fire ants would kill every last Pheidole. His expertise on Pheidole genealogy helped make that experiment and discovery possible in the first place. He had developed “a feel for the organism” (167). 

In another study, Wilson and some other researchers studied the proliferation of life on remote islands, especially Vanuatu and the Solomon Islands. Given the relative diversity of life on several islands, Wilson and his fellow scientists noted that Vanuatu seemed to be the youngest of the islands. Their findings tallied with those of geologists, lending credibility to both research initiatives.

Wilson tells one other story of his experiences as a scientist. Thanks to his thorough knowledge of ant species, he and his team were able to find evidence of an ant species once thought extinct. They were also able to find evidence that new environmental concerns (primarily an invasive species of fire ant) still threatened that species: Within a few decades, the ants might really go extinct. Governments in the area are now trying to protect the vulnerable species. No solution has yet been found, but Wilson is hopeful that the future might hold answers. These problems are serious, and they require a great deal of expertise and energy to solve. Young scientists can make a big difference if they are willing to help solve the issues of invasive species and environmental degradation that threaten biodiversity on Earth.