View a breakdown of the identified species on Earth, led by about one million insect species, while mammals such as humans make up one of the smallest groups.

At any given time, there are an estimated 10 quintillion individual insects alive on Earth.

Research suggests ants are the most abundant insect on the planet, with an estimated 2.5 million of them for every human on Earth.

Identify household beetles with this database

Beetles are the largest order of insects in the world, with over 400,000 described species. They are found on every continent except Antarctica, and in every habitat imaginable, from the deepest oceans to the highest mountains. A small percentage...

See how each of the more than 2 million known species relates to each other—and to common ancestors—in this zoomable tree of life.

According to the International Union for Conservation of Nature, as of 2025, there are over 18,000 endangered animal species worldwide, with the share of fish, insects, mollusks, and reptiles increasing since 2007.

Lining up every microbe on Earth would stretch to about 105,000 light-years

There are about 10²⁷ such organisms on the planet, many of which are adapted to produce energy through uncommon reactions in unconventional environments, such as within rocks or near volcanoes on the ocean floor. Studies of these organisms have reframed astrobiologists' search for life beyond Earth by broadening the parameters under which life can exist.

Visual deep dive into the collapse of insects

The most diverse group of organisms on the planet are in trouble, with recent research suggesting insect populations are declining at an unprecedented rate. Explore this visual interactive on the issue from Reuters Graphics.

Although ecologists have struggled to identify a species as a keystone—one of outsized importance to its ecosystem—an analysis of 50 years of data and 157 studies identified 230 such species.

As of 2022, scientists estimate that 117 billion people have been born on Earth

Although no demographic data exist for more than 99% of the time humans have existed, this value can be estimated by tracking approximate population sizes over different periods and the birth rates within those periods. In 2022, about 6.8% of humans that have ever been born were alive.

As of 2023, there are about 1.1 billion objects stored in 73 of the world's largest natural history museums, but only about 16% of specimens are available in digital archives.

Mammals gradually expanded in size and diversity after the dinosaur extinction

After an asteroid impact caused a mass extinction event 66 million years ago, small mammals were among the few surviving species. With fewer predators, mammals steadily grew larger as new habitats emerged.

Some mosquitoes are key pollinators—and eat disease-carrying mosquitoes.

Visualizing the 75 largest underwater animals

With so many fish in the sea, which are the largest? This infographic shows fantastic illustrations of the 75 largest sea animals, ranked by average size. The detailed visual is organized in descending order of size, starting with the blue whale,...

Scientists have found that the Great Barrier Reef's microbiome includes an estimated 362,802 distinct viruses and 876 distinct bacterial and archaeal species—584 of which had never been documented before 2026.

Based on a species' population size, distribution, and habitat, it may be designated as a threatened species—vulnerable, endangered, or critically endangered—if it is at high risk of extinction.

Contributing to one in every three bites of food consumed by humans, bees are a keystone species because of their essential role as pollinators of about 80% of all flowering plants worldwide.

View a sample of the bioluminescent tree of life

This diagram shows 42 different light-producing organisms, from bacteria and fungi to worms, fish, and crustaceans. It illustrates how the ability to produce light has appeared multiple times across the tree of life, rather than stemming from a single ancestor.

Humans may be able to distinguish more than one trillion scents

That's according to one estimate published in 2014. This figure far exceeds earlier estimates of a human smelling ceiling around 10,000 odors. The newer figure is derived from experiments in which volunteers agreed to sniff varying scents. Researchers mixed odor components and had volunteers sniff the brews to detect subtle scent differences. (Some users may experience a paywall.)

Explore a comprehensive encyclopedia of all known bird species and families.

A collection of fascinating facts about the planet and its creatures

You may have already heard that cheetahs are the fastest animals on land, but did you know that Savannah elephants are the strongest? This page on the World Wildlife Fund's UK website features a diverse range of articles on mammals, underwater creatures, birds, reptiles, insects, and landscapes. Discover captivating information about Earth and the creatures you share it with.

Humans may be the ultimate invasive species

Originating in East Africa, Homo sapiens migrated across the world beginning about 60,000 years ago and directly harmed countless species by consuming resources and modifying ecosystems to serve our needs. While meeting the definition of an invasive species, some ecologists argue the opposite, claiming that humans have helped preserve numerous species.

Desert wildlife: diverse, threatened, and misunderstood

This article sheds light on the surprisingly diverse wildlife that thrive in deserts, while also highlighting the gaps in human understanding of these ecosystems. Deserts are home to one-quarter of terrestrial vertebrate species—three percent of...

Watch David Attenborough's documentary on bioluminescent creatures, which have been observed using light for hunting, mating, communication, and self-defense, and number in the thousands of species.

Over 1,500 insect species pollinate plants in the UK

These insects—including bumblebees, moths, butterflies, and beetles—play a crucial role in the reproduction of flowering plants, also known as angiosperms. They do so by transferring pollen from the male reproductive organ—the anther—to the female one—the stigma—which enables the plant to produce fruit.

Explore the human family tree

This interactive human family tree shows the various species that constitute the human evolutionary family. Click on each species or group image to learn more.

More than 2 billion people across the globe include bugs in their diets

Entomophagy is the practice of eating insects. It has been around for millennia. Bugs are nutritious and, in some places, considered a delicacy.

There have been five mass extinction events in Earth’s history

Each extinction event has resulted in the loss of at least 70% of Earth’s species at the time of the event, often due to significant changes in global temperatures. The most recent event occurred 66 million years ago and wiped out all non-avian dinosaurs.

Where are humans on the evolutionary tree?

This interactive tree-shaped map explores the evolutionary connections between more than two million species. According to this map, humans are on the same branch as great apes, tarsiers, and treeshrews. That branch then splits into even smaller branches, with humans appearing on the same twig-like branch as chimpanzees and bonobos.

Less than 0.1% of the approximately 20,000 known bee species make honey

The majority of honeybee species originate in South and Southeast Asia, with the largest—Apis laboriosa—found almost exclusively in the Himalayas. The smallest is the black dwarf honeybee, Apis andreniformis, which inhabits tropical and subtropical regions of the continent.

Mosquitoes top the ranking of the world's deadliest animals.

These animals are only found in the Amazon rainforest.

The mighty Amazon River and its surrounding rainforest is home to millions of different species of animals, with new ones being discovered regularly.

View the biggest threats to biodiversity, according to the World Wildlife Fund, led by changes to species' environments, species overexploitation, and invasive species.

Mapping how human population has grown throughout history

It took 200,000 years for our human population to reach 1 billion—and only 200 years to reach 7 billion. When will our global population peak? And how can we minimize our impact on Earth's resources, even as we approach 11 billion?

Nearly 99% of the Smithsonian's specimens are hidden in high-security

At the National Museum of Natural History, nearly 99% of its 147 million specimens are stored in secure research collections rather than on display, where they are actively used for scientific work ranging from tracking invasive species to improving aviation safety.

Watch every episode of David Attenborough's 'Life on Earth' series

A three-year global expedition by Attenborough and his team produced the television series, which debuted in the UK in 1979 and documented over 600 species in 40 countries. The series is estimated to have been seen by over 500 million people in more than 100 territories, including within the US, where is debuted on PBS in 1982.

What if we killed every mosquito on Earth?

Mosquitoes aren't just annoying, they're deadly. they're also responsible for an estimated 725,000 deaths worldwide, every year. Would it be so bad if we found a way to wipe them out completely? Real scientists have gamed out this hypothetical scenario, concluding it actually wouldn't be that bad. This five-minute video breaks down one way this could happen.

Why scientists are making robot insects

Insects have much to teach us about flying, jumping, moving quickly, and more. So, roboticists are studying how insects do the ridiculous things they do, like walk on water or jump fifty times their body height, to inform their design and engineering of a new slate of robots: tiny ones. Learn the future of this type of robot with this fascinating video with insights into both insects and robots.

Visualizing the built world compared to the natural world

In the last century, humans have covered the Earth in 1,300 metric gigatons of built material, known as technomass. That amount is more than the Earth's entire biomass at 1,100 GT, which includes all living organisms. To get a sense of the scale of this comparison, click through this striking, simple visualization showcasing the various organisms comprising biomass as well as the materials making up the technomass.

Some animals, including certain tropical ants, have little or no microbial populations in their gut, upending the idea that all animals rely on this ecosystem to help maintain their health and proper functioning.

Tracking butterfly migration via the pollen they collect

Trillions of insects migrate around the world each year, but many are too small to track with physical trackers, leaving their migratory routes a mystery. In recent years, scientists have utilized pollen grains collected from butterflies to analyze which plants that pollen originated from—providing substantial data to infer the insect's specific route. Research has shed light on many insects' migrations since, including the Painted Lady butterfly. Read more and see a map here.

Explore Santa Barbara County's biodiversity

As part of one of the world's most biodiverse hotspots, Santa Barbara County is home to thousands of unique species, the majority of which are not found anywhere else in the world. This database compiles facts, photos, and more for each species, sortable by plants, animals, and more.

About 1,500 species of tardigrades have been identified by their unique physiology

Freshwater-bound eutardigrades live on mosses and lichens and are distinguished by variations in the shape and number of claws at the end of their legs. Marine heterotardigrades, which live on algae and deep-sea sediments, have been observed to possess feathers, inflatable appendages, and flagpole-like tails.

From 1970 to 2017, invasive species have caused $1.28T in damage globally

The costliest species were the Asian tiger and yellow fever mosquitoes ($149B), which arrived in the US from Asia and sub-Saharan Africa, respectively. The bulk of their damage came from their transmission of diseases such as Zika, chikungunya, and dengue. (Some readers may experience a paywall.)

Human ancestors: a guide

Modern humans are not the only creatures classified as part of the Homo genus. This article examines the eight other humans that fall under the Homo umbrella.

Researchers generally group gut bacteria into six different categories, with varying amounts of these microbes residing in different parts of the digestive tract.

Although many insects are colloquially referred to as bugs, insects are only considered true bugs if they possess a proboscis—a straw-like mouthpart that can pierce surfaces and suck up fluids.

Mapping migrations of hundreds of bird species

The birds we see throughout the year are long distance fliers, often traveling over thousands of miles to reach optimal nesting grounds, better feeding, and more. This thorough interactive map tracks over 450 types of bird on their annual migrations, depicting both their route as well as some of the conservation hurdles each species faces. Fly along with your favorite bird here.

Estimates say 2.5 billion total T. rexes lived on Earth

Roughly 68 million years ago, the Tyrannosaurus rex was king of the North American ecosystem. Researchers used the dinosaur's size, metabolic rate, age of sexual maturity, and other factors to determine 20,000 individuals likely were alive at any given time, more than 120,000 20-year generations. This piece breaks down how they arrived at those numbers.

Infographic illustrates the diverse and fragile Amazon ecosystems

This infographic helps readers better understand the vast rivers, forests, plants, and animals that call the Amazon rainforest home. Home to the largest collection of plant and animal species in the world, the Amazon rainforest has 16 thousand known...

Metamorphosis evolved over millions of years as species that hatched as smaller versions of adults started exhibiting genetic mutations that differentiated juvenile and adult bodies.