Speculative biology is a subgenre of science fiction that imagines the evolution of life forms in a way that is not based on what we know about natural processes. It also explores the possibility of life elsewhere in the universe.
It focuses on hypothetical scenarios that could occur in evolution to create bizarre yet plausible looking forms of life. It is often used to depict futuristic worldbuilding and combines elements from astronomy, biology, ecology, and other sciences.
Speculations about the origins of life
The question of how life began is one of the most difficult problems in science. This is because there is no mechanism that would allow non-living matter to randomly spark itself into life.
The idea that life began spontaneously was a popular view among scientists until it was disproven in the late 1800s by Pasteur. In 1876, the French scientist published a paper that showed that microorganisms could not be born from nonliving matter. This was a shock to many, since it proved that life didn’t come from non-living things.
However, people weren’t ready to give up on the idea of spontaneous generation. In fact, a Greek philosopher named Anaximander believed that small animals such as fish and worms could be created from mud and other materials.
As time went on, people started to think that life began in a way that was very similar to how it occurs today. For example, they thought that small animals might have evolved from a single parent organism.
They also thought that animals might have been produced from a series of genetic mutations. It was these ideas that gave rise to the theory of evolution, which explained how species developed from simpler creatures.
But these theories still left open the question of how life began on Earth. There were plenty of fossils to find that could show how life changed over time, but there was no way to tell when the first living creatures appeared.
Eventually, researchers began to wonder whether the earliest forms of life might have been formed from simple organic molecules that came to Earth from meteorites. These could have been molecules that resembled proteins, DNA, or RNA.
Some scientists think that these molecules might have formed in the form of polymers. This is similar to the way that amino acids and small proteins can form polymers on early Earth under specific conditions (see below).
Others believe that these molecules might have been formed in the form of metabolic networks, which are similar to biological pathways but not as complex as proteins. These metabolic networks could have been the first to generate molecules that acted as catalysts to form larger and larger molecules.
Speculations about the nature of life
Speculations about the nature of life have played a central role in both science and philosophy for centuries. The earliest of these speculations was written by a thirteenth-century English bishop, Robert Grosseteste (known as the “Oxford” of his time), who believed that the universe was not made of eternal, immutable things but was, like the spirit, engaged in a process of a highly dramatic character.
The earliest forms of this kind of speculation were often called “metaphysical” because they did not take the form of observations based on empirical evidence, but were instead derived from the imagination. It was considered to be a “grandiose speculative construction,” and scientists of the time were quick to criticize it.
For example, it was thought that life on Earth arose gradually from inorganic molecules under reducing conditions, with the first organic molecules being self-replicating nucleic acids, such as RNA or DNA. In 1953, Stanley Miller and Harold Urey performed a simple experiment to test this idea, which provided the first evidence for the formation of organic molecules from inorganic components.
Since then, a number of different theories have emerged to explain how life on Earth may have originated. One of the most common is called the Oparin-Haldane hypothesis, which holds that life began as a stepwise, spontaneous formation of simple biological molecules or assemblies. Another is called the genes-first hypothesis, which posits that the first life forms were self-replicating nucleic acids.
A third is called the metabolism-first hypothesis, which posits the formation of biological molecules and organisms based on metabolic networks. This hypothesis is most widely accepted today, as it provides a more detailed account of the origins of life than either the Oparin-Haldane or the Miller-Urey hypothesis, and it offers a way to explain how simple life can evolve into complex life.
Achinstein has a lot of strengths here, but there are also several major problems. The most serious is that he gives far too much emphasis to the epistemic role of speculation, rather than the pragmatic role. He also seems to make the mistake of defining speculation in terms of evidence too heavily, leading him to appeal to philosophical conceptions of evidence quite a bit.
Speculations about the future of life
Speculations about the future of life may take many forms. For example, they may focus on how we might find and repopulate extinct species, or on whether life can survive long periods of time in space.
Often, speculations about the future of life are made with the goal of increasing public understanding and appreciation for biological processes and discoveries. This is particularly important for a science audience, as the world of science is changing rapidly, and new discoveries can be difficult to understand.
One of the most popular types of speculative biology is the study of hypothetical lifeforms that have evolved outside of Earth. This can include alien species, or creatures from another planet or solar system.
Another type of speculative biology is the study or reconstruction of prehistoric animals. This includes dinosaurs, pterosaurs, and other extinct critters. It also includes works that reconstruct ancient artifacts or historical events that are not currently recognizable.
It is also common to see speculative biology used to describe the origins of life or how it came about. For example, some scientists have proposed that life might have originated from a combination of chemicals in the atmosphere during primitive Earth’s early days. Other suggestions have included a chemical reaction that created oxygen from a mixture of hydrogen, ammonia, and methane.
Other notable speculative biosciences include xenology, the interdisciplinary field that aims to study the possibility of life elsewhere in the universe; and paleoart, which reconstructs prehistoric animals, such as dinosaurs and birds, using fossils and other archaeological evidence. Despite their popularity, these fields are still relatively young and lack a shared language and method. This is a problem, as a better understanding of these fields can help us better understand the evolution of life.
Speculations about the nature of the universe
During the 20th century, scientists and philosophers began to reevaluate the role of metaphysics in science. This included the use of speculation, which was previously considered illegitimate and outmoded (Alexander 1963:187; see also Braun 1981).
Scientists can speculate about the nature of the universe in many ways. For example, scientists estimate the age of our galaxy and solar system using astronomical measurements. They also use physics to understand how galaxies form and evolve over time, such as by measuring the velocities of distant stars and galaxies.
According to the most well-known scientific theory, the universe was initially much more condensed than it is today. A giant explosion, known as the Big Bang, then sent matter expanding in all directions. This may explain why matter has a special physical attribute associated with life, namely that it can undergo nuclear reactions to produce energy.
While these theories have led to interesting results, they are speculative and therefore remain unknown. Consequently, some scientists question whether they are worth investigating.
For example, some researchers are suspicious of a new formula by Jeremy England, a theoretical chemist, that suggests that the driving force behind a class of phenomena in nature, including life, is a chemical process. The formula, if accepted, could be a major breakthrough in the study of biology.
It is important to note, however, that a theory such as England’s is not necessarily a speculative hypothesis. Rather, it is a hypothesis that provides a theory of how to interpret observations that are not otherwise explained by the accepted scientific model.
As Kuhn and Popper have pointed out, speculation can be defined as an effort to generate a new and challenging theory. This is necessary for scientific discoveries and can help scientists to develop new ways of thinking.
In addition to the role of speculation in theory development, it can also have an effect on how we assess the evidence and make decisions. For instance, when a new theory is introduced, it can be used to challenge existing ideas about the world, which can lead to more open discussions and a stronger understanding of the truthfulness of the underlying science.