According to a new scientific study, the approximately 7.6 billion human beings that inhabit our planet represent only 0.01% of all living beings on Earth. Despite this, we have led to the disappearance of 83% of wildlife and halved the plant biomass.
“This inadvertent killing has had a massive effect on the entire biosphere of our planet, leading to a situation where scientists say we are now in the middle of an almost unprecedented mass extinction,” reports Science Alert.
The 7.6 billion human beings who populate our planet represent only 0.01% of all living beings on Earth, according to a new study published in the scientific journal Proceedings of the National Academy of Sciences. In other words, if you classify humans in a light to heavy weight category, humans would barely make the light weight category.
But despite this, we have succeeded (and continue to succeed) in destroying much of life on Earth.
“I hope this will give people a panorama of the very dominant role that humanity now plays on planet Earth,” said Ron Milo, biologist at the Weizmann Institute of Science in Israel, at Guardian.
According to the study, since the beginning of civilization, humanity has led to the extinction of 83 per cent of wildlife (including 80 per cent of marine mammals and 15 per cent of fish). In addition, our civilization has cut plant biomass in half, at the same time encouraging an overabundance of domestic animals, 14 times more numerous than wild animals. This scientific work consists of a first complete inventory of life forms on the planet (biomass) and is based on the carbon footprint left by all living beings.
Among the conclusions of the biologist Milo, although bacteria are one of the most abundant forms of life (13% of the total), they are not, as is often thought, the ones with the most presence. Position number 1 belongs, by far, to plants, since they represent 82% of all living matter on Earth. The rest, from insects and fungi to fish and mammals, represents only 5% of the world’s biomass.
“When I do a puzzle with my girls, there’s usually an elephant next to a giraffe next to a rhinoceros,” Milo metaphorizes to the Guardian. “However, if I tried to give them a more authentic sense of the world, it would be a cow next to a cow next to a cow and then a chicken.”
Milo and his colleagues have spent over three years collecting and combining the scientific literature on the biomass of our planet, in order to produce the most up-to-date and comprehensive estimate on the mass of all realms of life.
“We know that some viruses can cause cancer in humans by changing the environment in which they live (in the case, human cells) to make it more appropriate for themselves,” said Tuul Sepp, co-author of the study and postdoctoral researcher in a statement. “We do the same thing. We are changing the environment to better adapt to ourselves, while these changes have a negative impact on many species at different levels, including the likelihood of developing cancer”.
As noted by scientists in the article published in Nature Ecology & Evolution, humans modify the environment in such a way that it causes cancer in wild animals. An example of this influence is pollution of oceans, rivers and lakes, radiation from nuclear power plants, exposure to pesticides on agricultural land and pollution by artificial light.
In men, we also know that night light can cause hormonal changes and lead to cancer,” explains Sepp.
“Wild animals living near cities and roads face the same problem, there is no darkness anymore. For example, in birds, their hormones (the same hormones that are linked to cancer in humans) are affected by light at night.
“For me, the saddest thing is that we already know what to do. We should not destroy wildlife habitats, pollute the environment and feed wildlife with human food (waste),” Sepp adds. “The fact that everyone already knows what to do, but we don’t, makes the situation even more desperate.
Front page picture credit: WWF