3.5 billion years of evolution

What are the earliest traces of life on Earth? In what context did they appear? When did they appear? How did they change the composition of the oceans and atmosphere? When and how did life conquer the continents? What are mass extinction events? How many has our Earth experienced in the past? How did the different forms of plant, animal, fungal, and bacterial life gradually transform the surface of our Earth? What is the evolution of species? Have we managed to reconstruct the entire tree of life? The answers in pictures below.

sous-menu Life on Earth : Introduction|3.5 billion years of evolution|Human-Nature Cohabitation>The Anthropocene

« Under discreet surveillance »

This photograph was taken on spring in Revel (Haute-Garonne, Occitanie). It shows two azalea flowers in the shade of the spring sun - or rather, their pistils and stamens, whose respective shapes evoke a set of micro-cameras. Are they monitoring their surroundings? Read more ...

The pistils and stamens of two azalea flowers

« A new life chapter »

This photograph was taken on spring in Revel (Haute-Garonne, Occitanie). It shows a bird feather on a bed of clover illuminated by the timid spring sun. When animal meets plant... Read more ...

« Flower crisps »

This photograph was taken in early spring in Revel (Haute-Garonne, Occitanie). It shows a Forsythia bud opening in the spring sunshine. Read more ...

« Entering the light »

This photograph was taken at the very end of winter in Revel (Haute-Garonne, Occitanie). It shows the first bud opening in a hedge of shrubs exposed to the Sun. A sign of an early spring that leaves vulnerable to late frosts. Read more ...

Hatching of the first buds at the end of winter

« Immortals »

This photograph was taken on an autumn day on the shores of Lake Saint-Ferréol (Occitanie). It shows the moss, which the lower temperatures and higher humidity rate of the surrounding air have enabled to expand, until it covers the entire surface of this rock. Read more ...

« Air mass conflict »

This photograph was taken on a winter day from Revel (Haute-Garonne, Occitanie). On February 24, 2022, to be precise. The day Russia invaded Ukraine. A geopolitical event illustrated on that day by the opposition of the Cers (westerly wind) to the strong gusts of the Autan (easterly). Read more ...

« Shades of blue »

This photograph was taken on an autumn day in the vicinity of Collioure (Pyrénées Orientales, Occitanie). It shows the Pyrenees mountain chain in a bluish hue - a sign that the summer heat has gone for definitively. Read more ...

The Pyrenees mountain chain from Collioure

« Evanescent silhouette »

This photograph was taken on a spring day from Revel (Haute-Garonne, Occitanie). It depicts a series of wind-sculpted nebulosities, whose incessant displacements evoke the movements of an evanescent silhouette. Read more ...

Displacement of nebulosities in the sky of Revel

« Cloud and Rain »

This image was created by superimposing several photographs of the daytime sky taken from Revel (Haute-Garonne, Occitanie). It shows how the shape and color of the clouds change with the wind. The presence of grain in dark areas heralds future precipitation. Read more ...

« Black or White »

This photograph was taken on a winter day from the shores of Lac du Merle in Sidobre (Tarn, Occitanie). It shows the Sun, relatively low on the horizon, whose pale rays strike one of the rocks that dot the surface of the lake and are reflected on its surface. Read more ...

Reflection of the Sun on the surface of the Lac du Merle

« Storm warning »

This photograph was taken on a summer evening on the shores of the Lac du Salagou (Hérault, Occitanie). A stormy evening. The heat of the day has led to the condensation of thick clouds, which the glow of the setting sun tinted in a gradation of orange-red. Read more ...

« Plant symbiosis »

This photograph was taken on a spring day not far from the small village of Saint-Julia in the Lauragais region (Haute-Garonne, Occitanie). It shows a field of flax, whose plants coexist with poppy flowers. Hence small touches of red in this vast bluish expanse. Read more ...

« Thwarted love »

This photograph was taken on a spring day on the shores of Lake Saint-Ferréol (Haute-Garonne, Occitanie). It shows a group of weeping willows, their branches bending towards the ground as the vegetation develops. Read more ...

« The whirlwind of life »

This photograph was taken on a summer day in the Lauragais region (Haute-Garonne, Occitanie). It shows a meadow composed of multiple plant species - including flowers that pollinators regularly visit, despite the many gusts of wind. Read more ...

« The time for festivities »

This photograph was taken on spring from the town of Revel (Haute-Garonne, Occitanie). It shows the Montagne Noire overlooking the Lauragais, a vast cultivated plain adorned with numerous woods and copses. This is where the small and big wild animals hide. Read more ...

Sunrise from Revel, at the foot of the Montagne Noire

« Magnifying effect »

This photograph was taken on a winter evening from Saint Félix de Lauragais (Haute-Garonne, Occitanie). This small medieval village is a veritable balcony overlooking the Pyrenees, an ideal promontory from which to watch the sun disappear behind the mountain chain. Read more ...

« Alchemy »

This photograph was taken on a winter day from the Lauragais hills (Aude, Occitanie). It depicts the meeting of two air masses over the Ariège mountains: one from the Pyrenees, the other from the Mediterranean. Then follows this golden coloring. Read more ...

« Skyscraper »

This photograph was taken on an autumn evening on the Lauragais plain (Aude, Occitanie). It depicts a forest composed of various tree species, which the setting sun slowly plunges into darkness. Small rustling sounds indicate the presence of numerous animal species. Read more ...

« The shadow of a caress »

This photograph was taken on an autumn afternoon from Auriac sur Vendinelle, a small village in the Lauragais region (Haute-Garonne, Occitanie). It shows the low-angled rays of the sun - or rather, the shadows cast by partly bare trees on a thick carpet of glowing leaves. Read more ...

« Cardinal points »

This photograph was taken on a summer afternoon in the Lauragais plain (Haute-Garonne, Occitanie). It shows a field of sunflowers whose flowers all seem to be pointing in the same direction. A cardinal direction. Yes, but which one? Read more ...

« The Wave »

This photograph was taken on spring in the Lauragais region (Tarn, Occitanie). Ploughing followed by sowing reveals a desert-like expanse. Or does this succession of hills and valleys rather evoke the breaking of one of the ocean's waves? Read more ...

« Autumn colors »

This photograph was taken on an autumn day on the Lauragais hillsides (Tarn, Occitanie). It shows the tree layer tinged with red, yellow and green. The glow of these colors contrasts with the pale whiteness of the sky. Read more ...

« Groupies »

This photograph was taken on a summer day in the Lauragais region (Haute-Garonne, Occitanie). It shows a field of onions in bloom in the setting sun. Read more ...

« Live and Become »

This photograph was taken on an autumn day in the gardens of the Château d'Auriac sur Vendinelle (Haute-Garonne, Occitanie). It reveals the different colors displayed by the leaves of the same tree, ranging from green to red through orange. Read more ...

« Azure blue »

This photograph was taken on an autumn afternoon in the gardens of the Chateau de Couiza (Aude, Occitanie). The Autan wind has swept the leaves from the trees, revealing the blue of the sky. Or rather, various shades of blue - from the horizon to the zenith. Read more ...

« Another world »

This photograph was taken on a summer day on the banks of Lac du Merle, in the Sidobre region (Tarn, Occitanie). The addition of an infrared filter radically transforms this summer landscape, giving the trees white foliage and the rocks the ability to float. Read more ...

« The cradle of humankind »

There are fractures in continental rock that foreshadow the destiny of a species. In this case, the human species. Like the great East African rift that stretches from the Zambezi to the Red Sea. This is precisely the region evoked by the crossing of the Terres Rouges in the Upper Aude Valley (Occitanie). Read more ...

The Terres Rouges of the Upper Aude Valley

« A giant with a foot of granite »

Imagine a 780-ton block of granite resting on an off-center bedrock, modest in size and similar in shape to an elephant's foot. Its name: Peyro Clabado, from the Occitan Pèira Clavelada, literally « nailed stone » (Tarn, Occitanie). Read more ...

« Via Petrae » (Stone path)

The Sidobre, a mountainous enclave located at the south-western edge of the Massif Central (Tarn, Occitanie). The autumn sun's pale rays caress the green and red foliage of the trees lining the forest. It highlights the rocks that dot and line the forest path. Read more ...

« Plumage is not ramage »

The colors of the stone, the reflections of light, reveal every detail of this fossilized dinosaur, including traces of feathers on both sides of its skeleton. This aspect explains the reason why this Archaeopteryx exposed at the Dinosaur Museum in Esperaza (Aude, Occitanie) was long considered as the common ancestor of all birds that now inhabit our Earth. Read more ...

An archaeopteryx at the Museum of the Dinosaurs of Esperanza

« Once upon a time the living ... »

This image results from the superposition of two photographs taken, the one inside the Giant Chasm of Cabrespine, the other one near the Pic de Bugarach (Aude, Occitanie). The figuration of volutes of starry gas on both sides of the limestone concretions evokes the smoke from hydrothermal vents, these fireplaces that cover the bottom of the Earth's oceans. Read more ...

« The brain of Neptune »

This photograph was taken at the Toulouse Natural History Museum (Occitanie). It shows the skeleton of a marine animal known as an anthozoan. Grouped in colonies, they cover the seabed and contribute to the building of the most extensive terrestrial structures: corals, polypiers, atolls, etc. Read more ...

« Cambrian art »

This photograph was taken at the Toulouse Natural History Museum (Occitanie). It shows a rock fragment composed of the skeletons of marine animals (trilobites, starfishes, sea urchins, etc.) dating from the Cambrian period, when life forms multiplied and diversified. Read more ...

« A stone book »

This photograph was taken at the Toulouse Natural History Museum (Occitanie). It shows the footprints of batrachians frozen in a rock discovered at Saint-Affrique (Aveyron, Occitanie). Together, these traces form a stone book, the reading of which provides us with information on the evolution of life on Earth. Read more ...

Batrachians' footprints frozen in a rock