We Know Zilch About 99 Percent Of 1 Trillion Species That Inhabit Earth
There could be as many as 1 trillion species on Earth but we know less than 99 percent of them, a new study suggests.
Researchers at Indiana University concluded that our biological knowledge is restricted to 5.6 million species but there could be upwards of 1 trillion species. The estimation was based on scientific and governmental databases and ecological models. Data from about 35,000 locations excluding Antarctica was factored, reports UPI.
"Estimating the number of species on Earth is among the great challenges in biology," study author Jay Lennon said. "Our study combines the largest available datasets with ecological models and new ecological rules for how biodiversity relates to abundance. This gave us a new and rigorous estimate for the number of microbial species on Earth."
In the data sources which provided the count of known species including flora, fauna and microbial life, around 20,376 microscopic species and 14,862 representatives of trees, birds and mammals.
To develop scaling models in order to estimate the total number of species on the planet, researchers identified trends.
"We suspected that aspects of biodiversity, like the number of species on Earth, would scale with the abundance of individual organisms," said another author Ken Locey. "After analyzing a massive amount of data, we observed simple but powerful trends in how biodiversity changes across scales of abundance. One of these trends is among the most expansive patterns in biology, holding across all magnitudes of abundance in nature."
"We document a universal dominance scaling law that holds across 30 orders of magnitude, an unprecedented expanse that predicts the abundance of dominant ocean bacteria. In combining this scaling law with the lognormal model of biodiversity, we predict that Earth is home to upward of 1 trillion (1012) microbial species," researchers wrote in the journal PNAS.