Genomics: A Vital Tool for Tackling the Biodiversity Crisis

As the growing biodiversity crisis looms, scientists are looking to catalogue and characterise the genomes of all the species that make up the natural world, with new research by BGI Group demonstrating what is achievable through advances in genetic sequencing technology.

Ahead of the UN Biodiversity Conference in December this year, scientists are desperately searching for ways to address the growing nature crisis.

Globally, the average abundance of native species in most major land-based habitats has fallen by at least 20% since 1990. And the problem only appears to be worsening.

Critical to tackling species loss are projects such as the Earth BioGenome Project, which aims to sequence, catalogue and characterise the genomes of all the Earth's eukaryotic biodiversity in order to help us better understand and harness biodiversity.

Scientists are not only looking to sequence large, iconic species such as elephants and rhinos, but are also focusing their attention on the seemingly more mundane creatures that represent the bedrock of the natural world.

Take ants, for example. Ants play an essential role in ensuring soil can sustain life, while also ensuring dead leaves, insects and small animals do not litter the Earth's surface for perpetuity. Put simply, without ants, the world would be in a very precarious state, and yet we continue to know so little about them.

The Mysterious Social Behaviours of Ants

Give an ant colony a week and a mound of dirt, and they will transform it into a subterranean city. Working seamlessly together, the colony will shift specks of dirt, piece by piece, to engineer a complex structure of parallel levels, linked together with an intricate web of tunnels.

Each ant has a specified role - some are workers, some are soldiers, and some are gardeners. There is also a queen. But despite her title, she does not direct other ants or make decisions for the colony.

For centuries, philosophers, authors and scientists have questioned how thousands - and sometimes even millions - of individual ants can work together without any central leadership.

Scientists have searched unsuccessfully for chemical cues or other signals that the insects might use to coordinate behaviour. But new research using single-cell technology is beginning to reveal the secrets of ant social behaviour.

A team of international researchers, led by China's BGI-Research, used single-cell genomic sequencing technology to study the brains of ants for the first time. The research revealed the social division of labour within an ant colony is entirely determined by different specialisations of the brain between for example, worker ants, male ants and queen ants.

"What we discovered suggests that the social division of labour among individual ants is determined by the different specialisation of their brains," said Dr. Li Qiye, first author and researcher at BGI-Research. "We humans learn and train ourselves to do different jobs, while ants are born with a specific role in their colony."

The study, published in Nature Ecology and Evolution, helps us to understand at last how ants work together as one "superorganism", with ant brains varying significantly between various groups in a colony.

For example, the segment of the brain responsible for smell is far more developed in worker ants due to their need to search for food. Meanwhile, male ants have comparatively more optic lobe cells, which help them search for suitable mating partners.

The study also revealed the process by which gynes (virgin queens) transform into queens after mating, with the number of optic lobe cell groups decreasing as the queens adapt to the darkness of the nest.

"It is only the queens' cells that adapt and change over time," said Dr. LIU Chuanyu, co-author and researcher at BGI-Research. "For other members of the colony they don't change, so if you were born a worker ant you will always be a worker ant."

Sequencing Technology

The study was made possible through developments in advanced sequencing technologies, an area where BGI Group is a leader. With single cell sequencing technology, the scientists could study ant brains at a cellular level and produce comprehensive maps of the brain of all adult forms of pharaoh ants.

This represents an important breakthrough, as only through such a depth of understanding can we work to protect and conserve the whole spectrum of plants and animals that make up the natural world.

Scientists now hope to go one step further and use advancements in sequencing technologies to drive similar breakthroughs across the board, with projects such as the Earth BioGenome project set to play a critical role in helping us better protect and conserve the Earth's rich natural heritage.