Countless species, from disappearing fish in the oceans to vanishing birds and mammals on land are dying at alarming rates, signalling that Earth is undergoing a sixth mass extinction driven by human activity for the first time in history.

According to science, extinction is the death of the last member of a species, leaving none behind to reproduce. It can occur due to disease, old age, population decline, or other factors. Extinction impacts biodiversity, disrupts ecosystems, and ultimately affects human life as well. Throughout Earth’s history, extinctions have occurred frequently. Fossils once abundant in earlier geological layers, ranging from tiny marine organisms to massive dinosaurs are no longer found today.

Scientists believe that 99.9% of all animal and plant species that have ever existed have now become extinct. There’s a classification of extinction into four categories:

Biological extinction is the first irreversible decline until the eventual extinction of a species.

Ecological extinction is the restriction to low abundance.

Local extinction is the disappearance from a particular study site of a species of plant or animal, but still present elsewhere.

Mass extinction is a process wherein a species disappears much quicker than it can be replaced.

Mass extinction is much rarer than other kinds of extinction and can only really occur when a big disaster happens. Mass extinctions are seen as periods during which extinction rates greatly exceed the “normal” rates. They are defined by two characteristics: magnitude and rate. The magnitude is the fraction of the extinct species, while the rate is the speed with which things happen. In approximately 4.5 billion years of Earth’s existence, this biological catastrophe has happened only five times:

• Ordovician-Silurian (444 million years ago): Killed many marine creatures and wiped out 85% of species on Earth.

• Devonian (365 million years ago): Killed many marine invertebrates and wiped out 75% of species on Earth.

• Permian-Triassic (250 million years ago): The largest mass extinction event in Earth’s history affected a range of species. Over 95% of species on Earth died in what was either a volcanic explosion or an asteroid striking the Earth.

• Triassic-Jurassic (210 million years ago): Killed many types of dinosaurs and wiped out 80% of species on Earth.

• Cretaceous-Tertiary (65 million years ago): Killed the remaining dinosaurs and wiped out 78% of species on Earth. Dinosaurs went extinct about 65 million years ago in that phase.

All five major mass extinctions were triggered by catastrophic events such as rapid climate shifts, massive volcanic eruptions, asteroid impacts, and resulting environmental collapses that devastated ecosystems and wiped out a vast majority of species on Earth.

At this very moment, the sixth mass extinction is likely underway but unlike all those before, this one is driven entirely by human activity. Amphibians, such as frogs and salamanders, are vanishing at staggering rates. Coral reefs, ascradles of marine biodiversity are dying due to warming oceans and acidification. Large mammals like elephants, rhinos, giraffes, and big cats (including tigers, lions, and leopards) are being pushed toward extinction by poaching, habitat loss, and human-wildlife conflict. The vaquita, a small porpoise in the Gulf of California, is on the brink of complete extinction, with fewer than ten individuals remaining. Pollinators such as bees and butterflies are in sharp decline, threatening the foundation of global agriculture and food systems.

But this extinction crisis is not just about wildlife, it is deeply tied to our everyday lives. The forests that are being destroyed are the lungs of the Earth, producing the oxygen we breathe and storing carbon that helps regulate our climate. Pollinator loss threatens the fruits, vegetables, and grains we rely on. The collapse of marine ecosystems could erase key sources of protein for billions of people. As ecosystems unravel, so too do the systems that purify our water, stabilize our soils, and protect us from floods and disease outbreaks.

Jaquelyn Gill, a paleoecologist at the University of Maine, explained, “We are in this unusual position where, for the first time, we are attempting to put our finger on a geologically superlative event while it is happening.” According to Professor Stuart Pimm of Duke University, “It is an event that has yet to come into being, we are virtually standing on its precipice.”

While researchers may debate specific definitions or timelines, today’s alarming extinction rates leave little doubt: we are witnessing a biodiversity crisis unlike anything seen since the last mass extinction, 65 million years ago.

This time, human actions are the root cause, and the damage is widespread:

• Habitat destruction: through deforestation, urban sprawl, agriculture, and mining wipes out the homes of countless species.
• Pollution, including plastics, pesticides, and industrial chemicals, poisons ecosystems.
• Overexploitation, such as overfishing and illegal wildlife trade, pushes species toward extinction.
• Climate change, caused by greenhouse gas emissions from burning fossil fuels, is rapidly altering habitats, making it hard for species to adapt.
• Invasive species, introduced by humans, often outcompete or wipe out native species in delicate ecosystems.

 If the sixth mass extinction truly unfolds, the planet will be plunged into chaos. Entire ecosystems will collapse as species vanish one by one, unraveling the delicate web of life that sustains us all. Food supplies will dwindle, economies will falter, and the air and water we depend on will grow toxic and scarce. This isn’t just the loss of animals and plants, it’s a looming catastrophe that threatens humanity’s very survival. The time to act is now, or we risk condemning the Earth to a silence from which it may never recover.