A Short History of Nearly Everything

by

Bill Bryson

A Short History of Nearly Everything: Chapter 23 Summary & Analysis

Summary
Analysis
London’s Natural History Museum is full of back corridors where scholars study samples—the museum contains over 15 miles of jars and folders containing everything from mollusk shells to pressed plants. Some scientists spend years studying one plant alone. Bryson enters the botany department and meets Len Ellis, who works as a curator of “bryophytes,” or mosses. There are 10,000 known moss varieties, though in the tropics more species are found each day. In fact, Ellis says that he has “no idea” how many species of moss live on Earth, though he thinks there are many more than the ones scientists have already discovered.
Bryson shifts to discussing Earth’s current biodiversity in order to stress that even when it comes to getting a full scientific grasp of the life that’s currently on Earth—even land life, which humans have the closes access to—scientists are limited in the knowledge they’ve gathered so far. The number of plant species alone that exist is so vast that scientific discovery has an extremely long way to go in identifying them.
Themes
Science, Discovery, and Mystery Theme Icon
It takes about six months to catalog a new moss once it’s been discovered, and these species often disclose new mysteries. The London Natural History Museum has 780,000 moss samples so far, including 30,000 plant specimens from famous British botanist Sir Joseph Banks, who sailed to Australia with Captain Cook during the famed 1769 transit of Venus. In 18th-century Europe, plant collecting is a popular and lucrative recreational pastime, with new varietals earning handsome sums on the commercial market. To Bryson, the “volume of life on Earth” is “seemingly infinite.”
Bryson discusses mosses in particular to stress that scientists even lack an adequate picture of life on Earth when it comes to one sub-species of plant life. The “seemingly infinite” diversity of plant life on Earth shows that scientists’ work may never be done—especially as new species continue to evolve.
Themes
Science, Discovery, and Mystery Theme Icon
The sheer volume of species in the world (including plants and animals) demands a good classification system, or “taxonomy.” One such system is devised in the 1700s by eccentric Swedish botanist Carle Linné, who names weeds after people he doesn’t like. Linné dramatically simplifies existing species names, which are highly disorganized in his time. Linne is the first person to classify whales as mammals based on similarities in their respiratory systems. Today, nearly all of his names are still in use (with the exception of sexually vulgar ones, which he has a curious fondness for). Linné divides animals into six categories—mammal, reptile, bird, fish, insect, and worm—though it takes until 1902 for naming systems to be standardized on an international level. 
Bryson has stressed that functional descriptions and systems are essential for scientific progress when it comes to physical, chemical, and geological phenomena. Now, he stresses the importance of this activity for biological organisms. Bryson thus adds further weight to his claim about the necessity of good descriptions for the scientific endeavor. Linné’s contributions make some progress in this regard, but even his system can be improved upon, meaning that there is still a lot of work to do.
Themes
Science, Discovery, and Mystery Theme Icon
Writing, Wonder, and Inspiration  Theme Icon
Taxonomy is fraught with duplications, however, because many species look very similar. Scientists also often disagree on how new species should be classified. The renaming of “chrysanthemum” flowers to “dendranthema” (for consistency purposes) in the 1980s is met with such uproar that the International Association for Plant Taxonomy has to change the plant’s name back to “chrysanthemum” in 1990. Frequent disputes and reclassifications mean that “we don’t have the faintest idea” as to how many species of life there actually are on Earth—estimates range from “3 million to 200 million.” Moreover, scientists think they’ve only discovered three percent of Earth’s species. There are also disagreements within sub-categories: for example, some scientists think that there are 4,000 species of earthworm, while others think that there are 12,000.
Bryson stresses that when it comes to life on Earth, the task of generating clear and adequate descriptions is even harder, partly because of the sheer volume of species and partly because of how inconsistent classification systems have been in the past. There is thus a pressing need for good, clear classifications of biological life to help science in this area progress. The volume of life’s species provides further evidence that scientific knowledge about current life on Earth is highly limited, and it still has a long way to go.
Themes
Science, Discovery, and Mystery Theme Icon
Writing, Wonder, and Inspiration  Theme Icon
Get the entire A Short History of Nearly Everything LitChart as a printable PDF.
A Short History of Nearly Everything PDF
Estimates vary so much because it’s difficult to extrapolate from a sample to the world at large, and taxonomists often struggle to decipher 19th-century classifications when checking for duplications in historical publications. Bryson thinks we know “as little as we do” because of four reasons. First, most living things are very small. A typical mattress is home to 2 million microscopic mites, for example, though mites weren’t discovered until 1965. Bryson urges the reader to image how many equally small species exist in undiscovered parts of nature.
Another reason why scientific knowledge of current life on Earth is so limited is because most life is microscopic. This means that there is a lot of area to cover, implying that the scientific endeavor to catalog Earth’s life forms is going to take a very long time. It’s even difficult to know when a new species is discovered because historical classifications are often unclear. This further shows how unclear writing or systematizing can hinder scientific progress.
Themes
Science, Discovery, and Mystery Theme Icon
Writing, Wonder, and Inspiration  Theme Icon
Second, scientists often don’t look in the right places. Historical searches focusing on Europe and North America, for example, overlook rainforests, in which over half of animal life and over two-thirds of plant life live. At least 99 percent of flowering rainforest plants have never been tested for their medicinal properties (since plants can’t flee predators, they often have inbuilt chemical defenses with profound medicinal potential). Third, there aren’t enough specialists. Fungi, for example, don’t entice many researchers, meaning that only 70,000 of a potential 1.8 million species have been cataloged so far.
Bryson argues that scientific knowledge is also in its infancy when it comes to Earth’s life forms because many environments where the greatest biodiversity exists are underexplored, such as the planet’s rainforests. Scientific discovery also demands a lot of specialized human labor—far more than is presently available. Once again, Bryson emphasizes that scientists aren’t even close to learning all there is to know about life on Earth.
Themes
Science, Discovery, and Mystery Theme Icon
Finally, the world is huge—air travel and communication are deceptive compared to how much literal ground there is to cover. The flightless “tahake” bird of New Zealand was pronounced extinct 200 years ago, but it was recently rediscovered alive and well in a remote rugged area of the island. Discovering all life would demand upturning every single rock on Earth. New species are also often discovered living in places assumed to be inhospitable to life (such as blind, colorless insects that live deep underground). It would demand an array of specialists waiting to analyze all these curious species, all willing to devote decades to one varietal alone, and there simply aren’t enough people interested in doing that.
Bryson argues that scientific discovery of current life on Earth is only just getting started because there’s so much ground to cover. Even species that scientists believe went extinct crop up alive and well as scientists make more headway in exploring Earth’s land surfaces.  Humans may think we’ve conquered the globe, but this belief is deceptive—it will likely take scientists countless years to cover all the ground they need to, meaning that the majority of the scientific journey lies ahead of us.  
Themes
Science, Discovery, and Mystery Theme Icon