What is life? The question is dizzying, as it touches on both philosophy and biology. For centuries, humans have tried to understand what distinguishes a living being from an inanimate object. Life appears as a complex phenomenon, shaped by a multitude of parameters that sometimes make its origin, evolution, and forms difficult to define.
Despite this complexity, biology offers an operational definition: an organism is considered alive when it exchanges matter and energy with its environment, maintains a certain autonomy, reproduces, and evolves through natural selection. All living beings, from bacteria to mammals, ensure their stability by reacting to changes in their environment.
The study of evolution and traces of life allows us to retrace the history of life on Earth. Fossils, footprints, organic molecules, and microscopic structures bear witness to the successive transformations of organisms over billions of years. Understanding these traces means exploring the dynamics of life, its adaptations, its crises, and the mechanisms that have shaped current biodiversity.
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The Great Filter of Evolution: The Key to the Fermi Paradox 
Why Does the Sunflower Turn Toward the Sun? An Answer Through the Lagrangian 
World Population 2026: Demographic Trends by Continent 
Why Life Emerges from Imbalance and Dies at Thermodynamic Equilibrium 
The Electromagnetic Spectrum and Vision: What Our Eyes Perceive of Our Planet 
Self and Non-Self: A Simplified Physical Reading of Identity 
The Molecular Clock: From Random Mutations to Measuring Time 
White Sands Footprints: America's First Steps 
Hominins: Appearance, Expansion, and Extinctions 
Major Natural Disasters: What Are the Most Likely Threats? 
Major Civilizational Collapses: Key Periods and Causes 
Declining Births: Demographic Catastrophe or Natural Evolution? 
Natural Selection vs. Chance: Why Evolution is Not a Lottery? 
What if Life Originated from Earth? A Revolution in the Theory of Panspermia 
The Great Bifurcation that will Disrupt Our World: Survival or Collapse? 
Primordial Chemistry: Where Do the First Organic Molecules Originate? 
CO and CO₂: Two Gases, Two Risks, Two Biological Mechanisms 
Spontaneous Synchronization: A Universal Phenomenon, from Physics to Life 
Time Challenge: How to Illustrate a Billion Years? 
The Three Essential Components for the Emergence of Life 
Why Did the Genus Homo Nearly Go Extinct 900,000 Years Ago? 
The First Step Towards the Emergence of Life 
The shadow biosphere 
Decline of Anthropocentrism 
The horseshoe crab, a living fossil! 
Biosignatures or presence of life in the Universe 
Origin of life on Earth: Panspermia theory 
Origin of life on Earth: White smoker theory 
Why 37 degrees Celsius? 
Are We Alone in the Cosmos? Between Science and Speculation 
Traces of Life in the Ice: The Emergence of Prehistoric Mammoths 
The Younger Dryas: The Mini Ice Age That Wiped Out the Megafauna 
The Two Great Ice Ages: Surviving in the Oceans of a Frozen Earth 
Regeneration in Animals Following Amputation: Organic Regrowth 
At the Limits of Life: Mephisto, Worm of the Infernal Depths 
Discovery of solid buckyballs in space 
Human Walking: The Origins of Bipedalism in Hominids 
Karabo: A Window into Human Evolution 
Entropy: What is Time? 
The passage between the inert and the living 
The Great Story of Complexity: From Elementary Particles to the First Organisms 
Megapod uses volcanic heat 
Ardipithecus: The 4.4-Million-Year-Old Ethiopian Hominid 
Natural Selection: The Peppered Moth 
The Ordovician: The Era of Corals, Trilobites, and Graptolites 
Liquid Water, Much More Than a Solvent: A Catalyst for Chemical Reactions 
Neanderthal: Humanity's Lost Cousin 
Asimo the future humanoid 
What Conditions Allowed the Emergence of Life? 
Fermi Paradox and Plato's Cave: Are We Alone or Blind? 
Tardigrades: Indestructible Creatures That Defy the Laws of Biology 
Toumaï: One of the Oldest Known Hominins 
The Tree of Life: Billions of Extinct Species and a Single Ancestral Community 
Life in the Abyss: The Extreme Adaptation of Creatures 
Cyanobacteria and the Oxygen Crisis: A Primordial Ecological Catastrophe 
From Matter to Life: The Blurred Frontier of Biological Emergence 
The Smallest Frog in the World: Physiological Secrets of a Microvertebrate 
The explanation of the Little Ice Age 
The Light of Life: A Biosignature Revealed by the Moon 
Living Light: The Dazzling Secrets of Bioluminescence 
Beyond our senses, the great scientific revolutions 
The Primordial Soup: Chemical Cradle of Terrestrial Life 
World Population: From One Billion Humans to Demographic Saturation 
Ecology and Collapse: The Case of Easter Island 
Fractals:
Universally Self-Organized Structures