Ffrom the depths of the Amazon rainforest to the deserts of Antarctica, great questions remain unanswered about life on Earth. We asked leading scientists and conservationists: what’s the one thing you want to know about the planet that remains a mystery?
How many species are there on earth?
“How many different species of animals do we share the planet with? Estimates range from as few as 3 million to as many as 100 million, and there is little sign that we are yet converging on an answer.”
Prof Andy Purvis is a researcher at the Natural History Museum and a co-author of the 2019 UN global assessment of the planet
I would go back 540m years to see the ‘biological big bang’
“As an evolutionary biologist, I would love to have a time machine to go back to the Cambrian explosion [when most major animal groups first appeared in the fossil record] to see why this short period led to the really rapid rise of most animal groups, and why some like trilobites [extinct marine arthropods] did not survive.”
Evolutionary biologist Dr Corrie Moreau is an expert on ants at Cornell University’s Moreau Laboratory
Can some of the smallest life forms help prevent climate crisis?
“Just as we humans rely on our gut microbiomes for good digestion, the dirt under our feet contains a countless number of bacteria, fungi and viruses that affect the health of soil and the plants that grow in it. Because most of these organisms cannot be grown in the laboratory, we know very little about their ecology. Yet the presence of specific microbes can help trees grow to three times faster. Could these ‘good microbes’ be some of our best allies in fighting climate change and promoting food security?”
Dr. Bonnie Waring is a senior lecturer at the Grantham Institute at Imperial College London
What is the full biodiversity of the Amazon or Congo basin rainforests?
“I would like to understand the full diversity in a small area of tropical rainforest – like 100 by 100 meters: how many species live there or pass through, what interactions they have with each other, how old they are, where they come from , what they do. Beyond the scientific insights it would give us, I hope it will help convince people of the extreme complexity and value of ecosystems assembled over millennia – and that protecting what we have left is always a better choice than to later destroy and try to restore.”
Prof Alexandre Antonelli is the director of science at the Royal Botanic GardensKew
How do animals affect the workings of the earth?
“How do animals shape the appearance and function of ecosystems? We know they do this in some well-publicized ways such as pollination or seed dispersal, but there are many subtle ways – such as the cycling of nutrients, the selective eating of plants, the intricate webs of predators and prey – that are poorly understood. , but constantly surprised. Just last month I learned that spiders determine where plants grow and ecosystems recover after a volcanic eruption by trapping seeds in their webs. And finally, how much does this animal’s influence matter at the biome or global level? How much do animals shape the workings of planet Earth?”
Yadvinder Malhi is a professor of ecosystem science at the University of Oxford
What will happen to the Gulf Stream?
“If I had to know one thing that is uncertain at the moment, it is whether, and if so when, the gulf stream will suddenly shut down, completely changing the climate in Europe, causing a drastic drop in temperatures – with potentially catastrophic impacts on water and food security – while the rest of the planet bakes due to human-induced climate change.
Sir Robert Watson is one of the UK’s most leading climate scientists
Do universal rules govern how plants and animals develop?
“Organisms of many different lineages (including both animals and plants) appear to follow a limited number of common ‘styles’. What are the general, simple rules that govern the way they are ‘put together’, and what makes some of these styles much more successful on Earth than others? And if such rules exist, are they the same for animals and plants?”
Sandra Myrna Diaz is professor of ecology at the National University of Córdoba in Argentina
How many people could the earth support?
“The one thing I’d like to know is how much more people the earth can accommodate. At the current rate, it will take just 10 years to add another 1 billion people to the planet. We are already seeing the devastating impact of unsustainable human population growth as more people destroy pristine habitats for food and other basic needs leading to climate change and more frequent zoonotic disease outbreaks and pandemics. If we can live in balance, health and harmony with nature, how many more people will the Earth be able to accommodate?”
Which species will adapt to the climate crisis – and which will not?
“What are the limits of species adaptation and why? We know that the climate changes and species adapt, but we don’t understand what the limits are and why they vary. Which species will not adapt quickly enough and at what point? What will adapt and thrive – and what determines these responses? What can we do as a society to help species adapt? These are fundamental questions, the answers to which will determine what the natural world looks like in the future, but which also provide profound insights into how biology works and develops.”