Biological complexity: problem, define an individual (Introduction)

by David Turell @, Saturday, July 18, 2020, 23:33 (1376 days ago) @ David Turell

Apparently not easy as a part of biological philosophy:

https://www.quantamagazine.org/what-is-an-individual-biology-seeks-clues-in-information...

"At the core of that working definition was the idea that an individual should not be considered in spatial terms but in temporal ones: as something that persists stably but dynamically through time. “It’s a different way of thinking about individuals,” said Mitchell, who was not involved in the work. “As kind of a verb, instead of a noun.”

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"Many philosophers and biologists have taken up this “process view,” in which organisms and other biological systems exist not as fixed objects or materials but as flowing patterns and relationships in a river of flux.

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"Unfortunately, “once gene theory took over, it became a biology of things,” said Scott Gilbert, a developmental biologist at Swarthmore College. But now that’s starting to change again. “Twentieth-century biology was a biology of things,” he said. “Twenty-first-century biology is a biology of processes.”

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"Their formalism, which they published in Theory in Biosciences in March, is based on three axioms. One is that individuality can exist at any level of biological organization, from the subcellular to the social. A second is that individuality can be nested — one individual can exist inside another. The most novel (and perhaps most counterintuitive) axiom, though, is that individuality exists on a continuum, and entities can have quantifiable degrees of it.

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“'Think about building a kind of microscope which would allow me to see information being propagated forward in time,” Krakauer said. They described a mathematical framework that breaks information flows down into parts and evaluates individuality based on how different combinations of environmental influences and internal dynamics can predict a system’s future states.

"Based on these gradients of information flow, the Santa Fe team distinguishes three types of individuality. The first is the organismal individual, an entity that is shaped by environmental factors but is strongly self-organizing. Nearly all of the information that defines such an individual is internal and based on its own prior states. “This is a lens that, if you wore it, would allow you to see humans and mammals and birds,” Krakauer said.

"The second type of individuality is the colonial form, which involves a more complicated relationship between internal and external factors. Individuals in this category might include an ant colony or a spiderweb — distributed systems that are “partially scaffolded” by their environment but still maintain some structure on their own.

"The third type is driven almost entirely by the environment. “If you remove the scaffolding, the [entity] would fall apart,” Krakauer said. It’s like a tornado, which dissipates under the wrong temperature and moisture conditions. The very first life to arise on Earth was probably like this, Krakauer added.
way to think about biological units.

"Within this theory, individuals can be cells, tissues, organisms, colonies, companies, political institutions, online groups, artificial intelligence or cities — even ideas or theories, according to Krakauer. “What we’re trying to do is discover a whole zoo of life forms that extend far beyond what we have conventionally called living,” he said.

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"As an alternative, Ramstead is collaborating with Karl Friston, a renowned neuroscientist at University College London, to build a theory around Friston’s “free-energy principle” of biological self-organization.

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"The free-energy principle asserts that any self-organizing system will look as if it generates predictions about its environment and seeks to minimize the error of those predictions. For organisms, that means in part that they are constantly measuring their sensory and perceptual experiences against their expectations.

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"...attempts to use information flows, in theory or practice, to carve nature at its joints are “the beginning of sketching out ideas and concepts that could be potentially foundational for new areas of biology,” Hoyal Cuthill said.

"Laubichler agreed. “For the life sciences or biology to grow up as a scientific discipline,” he said, “it needs to do something like this.'”

Comment: I view this as over-analysis. Biology does not lend itself to physics, but the information biology uses runs biology.


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