Life on Earth Arose Multiple Times and in Multiple Ways, New Theory Says

Aug 17, 2021 by News Staff / Source

In a new theoretical paper, researchers from the Santa Fe Institute provide a new perspective on the origin of life by arguing that life has emerged many times on Earth and that there are many forms of extant life coexisting on a variety of physical substrate; to help explain this position, they organize theories of life into three dominant perspectives: extant centric, history centric, and principle centric.

Kempes & Krakauer argue for multiple forms of life realized through multiple different historical pathways. Image credit: Hadeano.

In their three-layered frame, Santa Fe Institute’s Dr. Chris Kempes and Dr. David Krakauer call for researchers to consider:

(i) the full space of materials in which life could be possible;

(ii) the constraints that limit the Universe of possible life;

and (iii) the optimization processes that drive adaptation.

In general, the team’s framework considers life as adaptive information and adopts the analogy of computation to capture the processes central to life.

“Several significant possibilities emerge when we consider life within the new framework,” Dr. Krakauer said.

“First, life originates multiple times. Some apparent adaptations are actually a new form of life, not just an adaptation. And it takes a far broader range of forms than conventional definitions allow.”

According to the authors, culture, computation, and forests are all forms of life in this frame.

“Human culture lives on the material of minds, much like multicellular organisms live on the material of single-celled organisms,” Dr. Kempes said.

“When we focus on the life traits of single organisms, we often neglect the extent to which organisms’ lives depend upon entire ecosystems as their fundamental material, and also ignore the ways that a life system may be more or less living.”

Within the team’s framework, by contrast, another implication appears: life becomes a continuum rather than a binary phenomenon.

By taking a broader view of life’s principles, the scientists hope to generate more fertile theories for studying life.

“With clearer principles for finding life forms, and a new range of possible life forms that emerges from new principles, we’ll not only clarify what life is,” Dr. Krakauer said.

“We’ll also be better equipped to build devices to find life, to create it in labs, and to recognize to what degree the life we see is living,” Dr. Kempes added.

Their paper was published in the Journal of Molecular Evolution.

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C.P. Kempes & D.C. Krakauer. 2021. The Multiple Paths to Multiple Life. J Mol Evol 89, 415-426; doi: 10.1007/s00239-021-10016-2