Life

The origin of life as seen by a geologist who loves astronomy

05-01-2025

THOMAS Pierre

Life on Earth was born about four billion years ago, shortly after the formation of our planet, 4.54 billion years ago. While the transition from…

Once upon a time when life appeared: chemistry in the earth’s ocean 4 billion years ago

05-01-2025

VALLÉE Yannick

Some 4 billion years ago, the Earth was largely covered by a huge ocean. This ocean contained a large number of small organic molecules, which…

Origin of the first cells: the engineer’s point of view

05-01-2025

DANCHIN Antoine

In a realistic scenario of the origin of life, a primeval metabolism begins in water at the surface of minerals. These promote the polymerization of…

Symbiosis and evolution: at the origin of the eukaryotic cell

05-01-2025

SELOSSE Marc-André, JOYARD Jacques

The cell of eukaryotic organisms (animals, plants, fungi) differs from that of prokaryotic organisms (Archaea and Bacteria) by the presence of several specialized organelles, such…

The dangerous liaisons of oxygen and life

05-01-2025

LEQRAA Naoual, VALLÉE Yannick

Oxygen is life! In any case today many biological processes could not take place without molecular oxygen, O2, and many organisms die when they are…

The biosphere, a major geological player

05-01-2025

THOMAS Pierre

The biosphere, that is, the terrestrial environment and the living organisms that have developed there, deeply shapes the planet Earth. With the genesis of carbonaceous…

The first complex ecosystems

05-01-2025

VANNIER Jean

Today’s ecosystems are amazing in the complexity of the interdependent relationships between the organisms that make up them. Energy and biomass circulate through food webs…

The first terrestrial ecosystems

05-01-2025

GUÉRIAU Pierre, MONDEJAR FERNANDEZ Jorge

The establishment of complex continental ecosystems is probably the most important event in the history of multicellular life after the Cambrian and Ordovician radiations that…

Massive extinctions in geological time

05-01-2025

LANGLOIS Cyril

At least five times in the past, a large number of species have disappeared in a short period of time [1]. The study of these…

Crude oil: evidences for its biological origin

05-01-2025

BAUDIN François

“Will the defendant please rise! Please state your first and last name, age and origin?” Petra Oleum, Old and Biological would answer all the crude…

What is biodiversity?

05-01-2025

JOYARD Jacques

Biodiversity concerns all living organisms, their interactions with each other and with their environment. All levels of life are concerned: from the gene to the…

Symbiosis and parasitism

05-01-2025

SELOSSE Marc-André, JOYARD Jacques

Living organisms are permanently closely associated with each other. Their interactions can be classified according to the level of association of the organisms involved, the…

Theory of evolution: misunderstandings and resistance

05-01-2025

BREGLIANO Jean-Claude

Modern evolutionary theory, based on Darwin’s work, constitutes a profound mental revolution for our representation of the world for at least two reasons. On the…

Lamarck and Darwin: two divergent visions of the living world

05-01-2025

BREGLIANO Jean-Claude

The last two decades have seen an accumulation of scientific data on so-called epigenetic phenomena, changes in the expression of genes induced by the environment…

Inheritance or convergence? The winding paths of species evolution

05-01-2025

MAZEL Florent, LAVERGNE Sébastien, DOUZET Rolland, THUILLER Wilfried

How can we explain that some species are more alike than others? Species are the product of their history: evolution. They represent the leaves of…

The adaptation of life to environmental constraints

05-01-2025

DESPRÉS Laurence

The diversity of living forms, or biodiversity, is reflected in phenotypic variations (expression of variable traits), themselves largely caused by genetic variations both within species…

The fixed life of plants and its constraints

05-01-2025

BRIAT Jean-François

Plants are fixed to the soil by their roots, which supply them with water and minerals, their leaves capturing solar energy to fix the carbon…

How do plants cope with alpine stress?

05-01-2025

STREB Peter, CORNIC Gabriel, BLIGNY† Richard

At high altitudes, plants can be subjected to strong constraints: high light and UV radiation, low CO2 concentration, large temperature variations… These parameters vary over…

Reproductive strategies of alpine plants

05-01-2025

TILL-BOTTRAUD Irène, AUBERT† Serge, DOUZET Rolland

When environmental conditions are difficult or peculiar, such as in high mountains, plants must adapt to ensure their reproduction. Two main strategies allow alpine plants…

DNA barcodes to characterize biodiversity

05-01-2025

POMPANON François, SHEHZAD Wasim

New high-throughput molecular biology techniques make it possible to identify species in our environment. By characterizing short fragments of DNA that persist in the environment,…

What biodiversity in the city ?

05-01-2025

MACHON Nathalie

Even if the urban environment imposes very strong constraints on the animals and plants that inhabit it, the biodiversity of our cities is rich in…

Dialogue and cooperation among bacteria

05-01-2025

LAMI Raphaël, TEYSSEDRE Anne

Are social communication and cooperation the prerogative of animals? Absolutely not: they also exist in plants and unicellular organisms, such as bacteria. Among the latter,…

Bats and viruses or how to live together in harmony

05-01-2025

LARCHER Gérald

Bats have long been ignored or even despised, and in recent years they have been the subject of increasing public and research attention. Endowed with…

Distribution of biomass on the planet

05-01-2025

JOYARD Jacques

What does the biosphere represent on Earth? How is the biomass distributed between oceans and continents? While hiking in the mountains, in the forest or…

What makes butterflies so colourful?

05-01-2025

DEBAT Vincent, ELIAS Marianne, LLAURENS Violaine

Butterflies, with their delicate patterns and bright colours, are the most popular of all insects. But beyond their beauty, what can the study of their…

Adaptation: responding to environmental challenges

05-01-2025

BREGLIANO Jean-Claude

Since Jean-Baptiste de Lamarck and Charles Darwin, we know that living beings were not created once and for all by a divine force to constitute…

The genome between stability and variability

05-01-2025

BREGLIANO Jean-Claude

The genome of living beings is permanently affected by anomalies, due to accidental errors or agents inside and outside the body. Fortunately, enzymes correct most…

Genetic polymorphism and variation

05-01-2025

VEUILLE Michel

Genetic polymorphism is the existence of alternative states of DNA, determining the variation of the organism’s higher levels of integration. There are different kinds of…

Genetic polymorphism and selection

05-01-2025

VEUILLE Michel

Polymorphism has caused controversy about its role in evolution. But if it essentially follows a neutral evolution, it serves as a reference, in contrast, for…

Epigenetics: the genome and its environment

05-01-2025

KHOCHBIN Saadi

Modern biology is discovering so-called “epigenetic” mechanisms that allow the genome to modulate its functioning without modifying the information contained in the genes themselves. Knowledge…

Biodiversity responses to global changes

05-01-2025

TEYSSEDRE Anne

Deforestation, fragmentation and pollution of habitats, intensification of agriculture and livestock farming, urbanization, massive emissions of greenhouse gases into the atmosphere, acidification of the oceans,…

A carbon cycle disrupted by human activities

05-01-2025

JOYARD Jacques, SOMMERIA Joël

All living beings are built from carbon atoms. These are extracted from atmospheric CO2 by plants, algae and certain bacteria, using solar energy: this is…

Shedding light on photosynthesis

05-01-2025

JOYARD Jacques, MOROT-GAUDRY Jean-François

What is the most essential for life on Earth? Water, of course; but probably light too… and photosynthesis that enhances it for the benefit of…

The path of carbon in photosynthesis

05-01-2025

MOROT-GAUDRY Jean-François, JOYARD Jacques

How is the carbon from carbon dioxide – CO2 – present in the atmosphere integrated into the organic matter that makes up living organisms, the…

Effects of temperature on photosynthesis

05-01-2025

CORNIC Gabriel

Terrestrial plants are regularly subjected to strong temperature variations. These variations can reach an amplitude of 40°C or even more, both in polar regions and…

How to feed plants while polluting less?

05-01-2025

BRIAT Jean-François, LEMAIRE Gilles

Is it possible to fertilize crops while respecting the environment? This question, at the heart of our society’s environmental concerns, has no simple answer. Plants…

The tireless-quest for water by plants

05-01-2025

SAUGIER Bernard

How does water reach the leaves of large trees? What tricks do plants develop to cope with the lack of water? How does vegetation modify…

How do plants tolerate a salty diet?

05-01-2025

LUU Doan Trung

Soils can become naturally saline, for example due to sea spray. But they can also be saline due to human activities. The latter phenomenon is…

Plants that live on air

05-01-2025

BROUQUISSE Renaud, PUPPO Alain

Use nitrogen from the air to synthesize its essential biomolecules? Plants achieve this feat by establishing a mutually beneficial association with soil bacteria. After a…

Cellular impact of solar UV rays

05-01-2025

DOUKI Thierry

The Sun is essential to life, whether through photosynthesis in plants or the production of vitamin D in humans. However, it is a source of…

Light, vision and biological clocks

05-01-2025

LE TALLEC Thomas

Since life appeared on Earth, various selection forces have influenced the evolution of living organisms. Among these forces, light generated by our sun probably had…

Listening to cetaceans

05-01-2025

PATRIS Julie

From the famous modulated song of humpback whales to the ultrasound sonar of pink dolphins in the Amazon, the mammals inhabiting the oceans and rivers…

The flight of birds

05-01-2025

BLONDEL Jacques

The conquest of the air by animals is a remarkable evolutionary invention that opened fantastic opportunities for many animal groups, both invertebrates and vertebrates. A…

Plants water needs

05-01-2025

ITIER Bernard

Water is essential for plant growth. If there is a lack of rainwater -particularly in the perspective of climate change- what can man do to…

The root system of plants: from the shadows to the light

05-01-2025

GRONDIN Alexandre, GUYOMARC'H Soazig, LAPLAZE Laurent

Roots are a prime target for crop improvement towards a more frugal and environmentally friendly agriculture. However, root traits have long been neglected in breeding…

Role of forests in the planet’s carbon balance

05-01-2025

WIGNERON Jean-Pierre, CIAIS Philippe

On a global scale, forests are the main continental carbon sink. However, on a more local scale, while some forests are carbon sinks, others are…

The orientation of migratory birds

17-01-2025

BLONDEL Jacques

Birds face many challenges during their migrations, not least orientation. How do they set a course and stay on it, what landmarks do they use…

The Tara Oceans expedition explores the diversity of plankton

05-01-2025

VINCENT Flora, BOWLER Chris

The oceans cover two thirds of our planet, and they are where life was born more than 3 billion years ago. The ocean is a…

Corals: Ocean engineers are under threat

23-04-2019

COURTIAL Lucile, ALLEMAND Denis, FURLA Paola

Coral reefs are one of the most complex and richest ecosystems on our planet. They are based on a bioconstructed mineral (or biomineral) structure built…

Oysters: the little-known architects of coastal environments

10-12-2021

POUVREAU Stéphane, DI POI Carole, FLEURY Elodie, LAGARDE Franck

Oysters are essential marine invertebrates in our coastal ecosystems. These architects of the environment provide many ecosystem services while supporting a flourishing economic activity that…

Biodiversity on rocky coasts: zoning and ecological relationships

05-01-2025

MANNEVILLE Olivier

The Atlantic rocky coasts, subject to tidal sway, make it easy to observe the organisms that colonize them. Depending on the level and living conditions,…

Amazonia: a huge ecosystem in constant evolution

05-01-2025

PAVE Alain

The Amazon region is home to the second largest forest on the planet after the Siberian forest, but the first in terms of biodiversity. The…

Peatlands and marshes, remarkable wetlands

05-01-2025

MANNEVILLE Olivier

Peatlands are wetlands whose vegetation produces peat that is very rich in organic carbon. The quantity of water entering the system and its chemical quality…

Lichens, surprising pioneering organisms

05-01-2025

ASTA† Juliette

Remarkable pioneers, lichens have conquered the most extreme environments. They are able to grow on the rocks of alpine peaks or those of rocky coasts…

Microbes in extreme environments

05-01-2025

FRANZETTI Bruno

There are few sterile places on the planet. Glacial deserts, hot springs, ocean bottoms, hypersaline environments, rocks of the earth’s mantle… even these hostile environments…

Why is the tiger mosquito so invasive?

09-03-2021

SHERPA Stéphanie

Where do invasive species come from? How are they introduced? Increased trade has led to an explosion in the frequency of introduction of alien insects…

How do birds adapt to a changing climate?

05-01-2025

BLONDEL Jacques

What can be done, being a bird, to adapt to a climate that is inexorably warming? Three solutions: fleeing under milder skies, adapting locally or…

What is the impact of air pollutants on vegetation?

05-01-2025

GARREC† Jean-Pierre

Plants are at the forefront of air pollution because they are fixed organisms at the basis of the functioning of terrestrial and aquatic ecosystems. The…

When invasive plants also wander in the fields

05-01-2025

CHAUVEL Bruno

Biological invasions are easily perceived by the general public, who see the development of populations of exotic animals or plants on roadsides, ponds or urban…

Nitrates in the environment

05-01-2025

GERMON Jean-Claude

The agricultural origin of nitrate leaks into the environment is no longer disputed. It results from the natural functioning of the nitrogen cycle and the…

What is the ecological impact of light pollution?

05-01-2025

LE TALLEC Thomas

Light pollution is a phenomenon associated with the use of artificial lighting by humans. In fact, it alters the natural cycles of light and alters…

Climate change and globalization, drivers of insect invasions

05-01-2025

ROQUES Alain, AUGER-ROZENBERG Marie-Anne

Global warming and globalization of trade have a decisive impact on the geographical distribution of insects. There is an exponential increase in the establishment of…

Lichens and environmental quality

05-01-2025

ASTA† Juliette

Without structures insuring physical protection, like the plant cuticle, lichens are directly exposed to their environment. Rainwater and air directly enter the organism, dust is…

Collembola: actors of soil life

02-05-2019

SALMON Sandrine

An unsuspected diversity of invertebrates swarms under our feet when we walk on the ground in a forest, meadow or garden. Invisible communities are active…

Ants as sentinels of the impact of global change

05-01-2025

CORDONNIER Marion

Climate change and urbanization are determining factors in the distribution of species, dramatically threatening their persistence. Biological invasions modify the interactions between different species and…

The oyster, the sentinel of a coastline to be preserved

05-01-2025

HUVET Arnaud, SANCHEZ Wilfried, POUVREAU Stéphane, FABIOUX Caroline

In the category of marine molluscs, the oyster is an essential species of our French coasts and has strong economic and heritage stakes. An ingenious…

Alpine alluvial landscapes and biodiversity

05-01-2025

GIREL Jacky

Riparian vegetation communities along watercourse provide specific habitats at the land-water boundary, where water, sediment and energy flows interact with the vegetation itself. River dynamics…

Mathematical models can help to better manage fishing

05-01-2025

AUGER Pierre, LETT Christophe

Fishing provides an important part of the food for people in some developing countries. This can lead to a worrying cascade of overfishing, collapsing catches…

Impacts of agriculture on biodiversity and ecosystem functioning

05-01-2025

TEYSSEDRE Anne

Since its beginnings in the Neolithic period, the expansion of agriculture has been accompanied by technical innovations that have progressively increased agricultural yields and enabled…

Environmental constraints and oxidative stress in plants

05-01-2025

DIZENGREMEL Pierre

Plants cannot move and are therefore particularly exposed to environmental fluctuations and external attacks. Environmental conditions are very rarely optimal, leading to the concept of…

Plant resistance to stress: role of respiration?

05-01-2025

DIZENGREMEL Pierre

Yes, plants breathe! Their growth is the result of a delicate balance between the photosynthetic acquisition of carbon and the respiratory restitution of part of…

Fertilisers in France in the nineteenth century

05-01-2025

KNITTEL Fabien

In the nineteenth century, farmers used organic soil conditioners and/or fertilisers in varying proportions. In Western Europe, agricultural yields were insufficient to guarantee food security…

What is nature?

05-01-2025

DUCARME Frédéric

Nature is a common notion, which everyone is familiar with as long as we are not asked to define it. This is normal: there is…

The Great Green Wall: a hope for greening the Sahel?

05-01-2025

GOFFNER Deborah, PEIRY Jean-Luc

The Great Green Wall of Africa (GGW) is a pan-African initiative to combat desertification in the Sahara Desert and the Sahel. Originally conceived as a…

Restoring savannas and tropical herbaceous ecosystems

05-01-2025

LE STRADIC Soizig, BUISSON Elise

When people think of savannas, they think of the vast African landscapes where elephants, wildebeest, giraffes or lions used to roam. With the seasons, the…

How vertebrate extinctions threaten tropical forests

05-01-2025

ALBERT Sébastien

Most tropical trees produce fleshy fruits that are eaten by vertebrates (known as frugivores) that disperse plant seeds. The regeneration of tropical forests therefore depends…

The promises of ecological rehabilitation in port areas

05-01-2025

BOUCHOUCHA Marc, CARLIER Antoine, CURD Amélia

Can we remake what we have undone? The construction of ports in coastal areas leads on the one hand to a total and irreversible destruction…

Ecological networks: how to reconcile biodiversity conservation and land-use planning?

05-01-2025

CLAUZEL Céline

In the face of accelerating environmental degradation, biodiversity conservation can no longer be reduced to the simple protection of natural areas. Environmental policies are now…

Biodiversity is not a luxury but a necessity

05-01-2025

BLONDEL Jacques

Biodiversity, a contraction of the term “biological diversity”, appeared in the public sphere at the Earth Summit (1992). Two meanings are recognized in the word.…

Biofuels: is the future in microalgae?

05-01-2025

MARECHAL Eric

Are we at the end of fossil fuels (coal, gas, oil) and will we know how to do without them? What alternatives are we considering?…

Biodiversity and crop adaptation to climate change in developing countries

05-01-2025

THUILLET Anne-Céline, VIGOUROUX Yves

Global warming has accelerated since the 1970s. This climate change has a major impact on crops and threatens agricultural production. In the countries of the…