New research from the University of British Columbia (UBC) has found that life exists in all dimensions, but some dimensions are more popular than others.

First study of its kind published today (March 29) PLOS ONEAs a postdoctoral research fellow in UBC’s Department of Zoology, Dr. Eden Tekwa studied the body sizes of all living organisms on Earth and discovered an unexpected pattern. Contrary to what modern theories might explain, the biomass of our planet that makes up all living organisms is concentrated in organisms at both ends of the size spectrum.

D., lead author of The Size of Life and currently a research associate in the Department of Biology at McGill University. “The number of smallest and largest organisms is much greater than any other organism,” Tekwa said. “This appears to be a new model that is emerging and needs to be explained, and we currently don’t have any theory to explain it. Modern theories predict that biomass will be evenly distributed across all body sizes.”

These results not only challenge our understanding of the distribution of life, but also have important implications for predicting the effects of climate change. “Body size determines many global processes as well as local processes, including the rate of carbon uptake and how the functioning and stability of ecosystems can be affected by the composition of living things,” said Dr Tekwa. “We need to consider how the distribution of biomass by body size will change under environmental influences.”

D., senior author, assistant professor in Rutgers University’s Department of Ecology, Evolution, and Natural Resources. “Life surprises us all the time, including the incredible range of sizes,” says Malin Pinsky. “If the smallest microbe were the size of the dot at the end of this sentence, the largest living organism, the sequoia, would be the size of the Panama Canal.”

Dr Tekwa has spent five years collecting and analyzing data on the size and biomass of all species of living organisms on the planet, from small single-celled organisms like soil archaea and bacteria to large ones like blue whales and sequoias. . They found that preference for large and small organisms was common across all species and was more pronounced in terrestrial organisms than in marine environments. Interestingly, the maximum body size reached the same upper limits for many species and environments.

“The largest body sizes are seen in various species groups, and the maximum body sizes are all within a relatively narrow range,” said Dr Tekwa. “Trees, grasses, subterranean fungi, mangroves, corals, fish and marine mammals all have the same maximum body size. This may indicate a universal upper limit of size due to ecological, evolutionary or biophysical constraints.”

Dr. Tekwa was also able to uncover some interesting details about the distribution of life in different ecosystems. “Although corals are only found in a small part of the ocean, they appear to have approximately the same biomass as all fish in the ocean,” said Dr Tekwa. “This shows how important the balance of biomass in the oceans is. Corals support a wide variety of fish, so it’s really interesting that these two organisms have almost the same biomass.”

As for humans, we already know we have a relatively small biomass, but our size among all living things reveals our place in the global biome. “We belong to the size range that includes the largest biomass with a relatively large body size,” said Dr Tekwa.

Dr. Tekwa added that his findings will help in future studies of the evolution of Earth’s environment. “This allows us to move forward because it already underpins the current situation involving human influences,” they said. “For example, fish biomass is probably half as old as before humans, but as we go further and further back in geological time, these patterns become increasingly difficult to understand. This is really important empirical research. We make a big difference for people and society when we solve the challenges of sustainable development, and global environmental assessments, sustainable development should be an integral part of their efforts.”