2.2 Life at Different Scales Summary

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Cities are striking physical systems that are not predicated solely by physical rules. A city has an immense density of information with myriad interacting living processes, including people and physical structures. Algorithms and the exchange of information allow the city to run.
Like cities, social media like Facebook and Twitter can be represented by a network map with nodes and lines. Most of the connections are informational in nature and don’t necessarily mean physical interactions.
Network maps can also be drawn for animal families, such as macaques, revealing how they establish bonds, fight with each other, and form other social structures. Animals use this information for collective computation; an individual can’t understand the interactions of everybody, but they use the limited information they have to make decisions about their social structure.
Ants also make collective decisions without each individual knowing what is happening throughout the system. Even with each ant having limited experiences, the ants collectively make good-quality decisions.
Volvox is another example of collective behavior. It is a unicellular organism that behaves like a colony in which biological entities act on a larger scale than the individual components do.
Erwin Schrödinger posed the question: “How can the events in space and time, which take place within the spatial boundary of a living organism, be accounted for by physics and chemistry?”
The above examples hint to the idea that there is no fundamental unit of life. Rather, life is a collective property of systems resulting from the way information is exchanged among the individual components. Said differently, life is not a level-specific phenomenon.
There is a tension between exploring the scale at which life emerges (chemistry) and what life actually is (information processing that occurs across systems).
One of the biggest problems in astrobiology is how life looks fundamentally in different settings. From a chemistry perspective, we are limited in what we can say about universals; we only know the chemistry on planet Earth. An information-based approach to understanding life might be more applicable elsewhere.
It could also be useful to think about life at a planetary scale rather than a cellular scale. The planetary scale includes all the lower-level scales down to cellular and chemical.