GabyOur planet’s biodiversity is astonishing. Information exchange among organisms has always been central to life and evolution. Humans are part of that biological community — a community that depends on communication and understanding of the environment, whether it’s friendly chats over coffee, reading the news, or watching videos on social media. Meanwhile, humanity is also building the technosphere.
How to measure data of the biosphere and technosphere?
ScienceAlert points out that human data is currently only a small part of the planet’s information exchange. But that could change within a century, with human-made data taking a much larger share. If that pattern holds for any developed civilization, it might change how we search for extraterrestrial life.
It’s nearly impossible to accurately measure the rate of information exchange across Earth’s biosphere. But researchers can make rough estimates. The most practical approach is to look at the number of living cells and how much information each exchanges.
For example, several studies estimate the total number of prokaryotes — including bacteria — at about 10^29 cells. If each exchanges roughly 1 bit of information every three hours, that works out to about 10^24 bits of information exchanged every second across the planet’s biosphere.
By contrast, the amount of digital data exchanged by humanity — the technosphere — is easier to estimate. Internet traffic alone is on the order of 10^15 bits per second. That’s about one billionth the rate of the biosphere.
The technosphere is growing faster and may surpass the biosphere.
The biosphere is relatively stable over long timescales (aside from occasional mass extinctions), while digital data has been growing exponentially. If the technosphere keeps expanding at historical rates, it could surpass the biosphere in less than a century.
What does that mean for extraterrestrial civilizations? Whatever medium—chemical signaling, optical fibers, or electronic circuits—data creation and maintenance require energy. Today most of that energy supports biological information, but in the blink of a cosmic eye the technosphere’s data could dominate.
If that pattern is typical of advanced civilizations, then a planet with intelligent life will likely be dominated energetically by technology rather than biology. That suggests we should prioritize looking for artificial thermal signatures when searching for extraterrestrial civilizations.
Even without considering aliens, the technosphere’s growth will have big consequences for life on Earth. Humans already strongly affect the biosphere and the planet’s climate. If exponential growth continues, humanity will greatly reduce the resources available to non-human life. That’s something to pay attention to.
