Gaia, our planet, is alive and we are its spermatozoon, a new study suggests

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Tempo di lettura: 5 minuti

A Tomsk State University scientist proposes that human beings will reproduce Earth’s biosphere


A novel intriguing and provocative idea by an Italian biologist working at the Tomsk State University (TSU) in Russia, suggests that even without invoking teleology, so without any foresight or planning, our planet can be considered the same as a coevolutionary system analogous to a multicellular body: a super-unit of selection. Dr. Roberto Cazzolla Gatti, associate professor at the Biological Institute of the TSU, in a paper entitle “Is Gaia alive? The future of a symbiotic planet” – published this week in the scientific journal “Futures” (https://doi.org/10.1016/j.futures.2018.07.010) – described different situations according to which “Gaia”, our Earth, would be able to reproduce and to transfer her planetary genome to other uninhabited or inhabited planets. The scientist argues that Homo sapiens sapiens, the modern human beings, could act as germinal cells carrying a specific planetary genome, but it is unlikely for us to reproduce (or survive disconnected from Earth) on another Gaian system. As a spermatozoon, which loses its flagellum and acrosome while entering into the egg of another body, therefore changing its identity, a human being can be considered just as a carrier of its body’s (i.e., Gaia’s) genetic information, not of himself: a means more than an aim. Many other taxa could have evolved and been able to operate as germinal units of propagation, which might be the case on other Gaian planets.

Life affecting first the development of the planetary environment, which, in turn, affects the future evolution of life in a coevolutionary way is a well-established idea now. Nevertheless, with the proposal of the Gaia hypothesis by the British biochemist James Lovelock in 1972 (who substantiated the idea of “biosphere” proposed by the Russian scientist Vladimir Vernadsky), there has been widespread criticism related to teleology, the absence of natural selection at a universal scale, and the absence of planetary reproduction. However, even if some of the problems concerning the rationale of this hypothesis have been resolved, it was unclear whether Earth can be considered a unit of selection and, therefore, Gaia can adapt according to Darwinian evolution. After Lovelock, the American microbiologist Lynn Margulis proposed that Gaia is a symbiotic planet composed of biotic (the biosphere) and abiotic (the geosphere-atmosphere) interacting with and coevolving elements.

Now, Prof. Gatti’s breakthrough in astrobiology dismissed the criticisms and argues that our species can indeed act either as a germinal cell, transferring Gaia’s genome and allowing her reproduction, or – if it continues to grow unconditionally and to consume the fundamental resources for the survival of the other components of the biosphere – as a cancer cell, impairing Gaia with a disease on her somatic cells (other taxa) and organs (ecosystems). This, subsequently, will affect her germinal cells (human beings themselves), preventing her from any possibility of reproduction (apart from an accidental spread due to asteroids impacts).

The biologist at TSU took into consideration the main concerns raised on the Gaia hypothesis and analysed them following a logic-deductive reasoning together with thought experiments (following Albert Einstein’s pathway to discovery), sometimes adopting analogical arguments (as the ethologist Konrad Lorenz was used to do). In his new paper in Futures, anticipated in a preliminary idea published in the journal Theoretical Biology Forum (110(1-2): 25-45, 2017), Roberto Cazzolla Gatti showed why and suggest how, a Gaian system, considered as a “symbiotic planet” composed by biotic (the biosphere) and abiotic (the geosphere-atmosphere) interacting and coevolving elements, should be considered alive in an evolutionary sense.

He proposed that Gaia can face exclusion-competition-coexistence states depending on the fitness of her biota compared to those of the other reproducing biospheres. This demonstrates that Gaia can reproduce and evolve in competition-cooperation with other planets. Some deep implications arise from these pieces of evidence in the light of the recent discovery by NASA of new solar systems with Earth-like planets.

“Our species, – declared Prof. Gatti – as a result of billion years of symbiotic evolution and differentiation within Gaia, has the possibility and the privilege to allow Gaia’s continuation, evolution and reproduction. This result could be achieved only if we keep biodiversity and ecosystems, living within Gaia, healthy, and we continue to study and protect them because they are the supporting and essential components of the body of Gaia”. Moreover, continues the Italian ecologist, “we should put efforts into the search for other Gaian planets in the Universe and, more importantly, into the technological advancements to transfer Gaia’s genome on other potentially suitable reproductive sites (uninhabited and/or potentially inhabited planets)”.

Since our planet is at three-quarter of its lifespan (1.75-3.25 billion years are left before the sun heats up so much to impede life on Earth; Rushby et al. 2013) and we are not able to transfer Gaia’s genetic information on other potential planets yet, there is another reason why we need to allow Gaia to live as long as possible: taking enough time to develop technological means for this purpose, suggest Prof. Gatti’s revolutionary paper.

“We need to start a specific research program divided in two phases, – says the TSU’s professor – to search for the most suitable, diverse and genetically representative mix of Gaia’s microorganisms that are likely to survive, evolve and reproduce on other planets (methanogens, extremophiles, phototrophic and chemotrophic bacteria, etc.) that can be transferred in what I called “biophore” (from the Greek: βίος, “life”, and φορά, “to carry”; i.e., a conveyor capsule of life). Furthermore, it is necessary to invest in the development of technologies that are able to transfer the “biophores” over long distances. This transfer can be either direct (if human beings are able to carry the biophores directly on the other planets), or indirect (if the spread occurs by the means of technological devices – a sort of artificial extensions of human beings, as Gaia’s germinal cells); either passive (if the dispersion is made without recipient targets, such as plant seeds dispersed by wind), or active (if the biophores are delivered on suitable planets detected beforehand)”.

According to some scientists, there are at least half a million Gaian planets just in the Milky Way. This means that there are many potential mates for Gaia, scattered everywhere, according to Roberto Cazzolla Gatti’s new idea. Therefore, millions of uninhabited planets could be suitable for Gaia reproduction.

Recently interviewed about how he came up with this idea, Prof. Gatti declared: “Paraphrasing Newton, to see further I only tried to standing on the shoulders of giants such as James Lovelock, Lynn Margulis, Albert Einstein and Konrad Lorenz. By adopting their ideas and their way of reasoning, I had an eureka moment about the future of our planet, our species and all living beings with which we share the Earth. As a cell of Gaia’s body, we have an important responsibility and we should act to keep her alive and reproduce her biosphere in the Universe”.

The road to exoplanets exploration and panspermia has now been marked. NASA and other space agencies have a new astrobiological mission to address. At the same time, we – as sperm cells of our planet, i.e. a fundamental component of its reproductive system – could finally find a meaning in our life and a purpose in the Universe.

Tomsk State University’s Press Office