We’re in the middle of a sixth mass extinction, and we’re currently losing animal species at 1,000 to 10,000 times the typical rate.
Animal species all across the globe are on the brink or already gone – and whether a majestic lion or a tiny snail, every single one matters.
We can all help in some way, even by starting with a single change. The first step? Educating ourselves. We’ve compiled in-depth information about these animals. Track the trends, examine the timelines, and think about these creatures.
Let’s save this planet before it’s too late.
All organisms in the animal kingdom are sorted into groups, each more closely related:
- Phylum: a broad group
- Class: a fairly large group
- Order: a smaller group
- Family: a group of closely related animals
- Genus: a group of quite closely related animals
- Species: animals so similar that they can interbreed*
*asexual species are classified by body shape
Interactive: Extinct Animals
Dig deeper into the world of extinction broken down by phylum, class, order, family, genus, and species in the interactive feature below.
A Planet in Crisis
Creatures within the animal kingdom are divided by phylum according to their distinct characteristics. We focused on the five most significant phyla when it comes to extinction.
- The Chordata phylum covers animals that at some point exhibit four features: a notochord (support rod), pharyngeal slits, a dorsal nerve cord, and a post-anal tail. This covers vertebrates (creatures with backbones), including amphibians, birds, fish, mammals, and reptiles, as well as some invertebrates (certain small marine animals).
- The Mollusca phylum features mollusks, which are soft with a “head” and “foot” region: chitons, clams, mussels, octopi, oysters, scallops, snails, slugs, and squid.
- The Arthropoda phylum incorporates arthropods, with exoskeletons, segmented bodies, and jointed legs: arachnids, crustaceans, and insects.
- The Annelida phylum covers segmented worms, including earthworms, leeches, and various marine worms.
- The Platyhelminthes phylum incorporates the simple animals with no anus or body cavity except for the gut: soft, flat-bodied worms, including planarians and tapeworms.
Animals from each phylum are further broken down into classes. Examining extinction by class reveals that gastropods (snails and slugs) have taken the hardest hit, followed by birds, fish, and mammals. The majority of each of the most at-risk class’s extinctions have occurred relatively recently, in the 1900s.
Nearly three-quarters of North American freshwater snail species are at risk of extinction due to habitat destruction, including pollution, damming, and channelization. Bird species around the globe are on the brink, due to loss of breeding ground, hunting, and chemical herbicides. Ray-finned fishes – 95% of fish, including tuna and virtually all tropical fish – face threats from non-native species, climate change, overfishing, and pollution.
Despite their resilience and versatility, birds are experiencing a terrifying free-fall, due not only to loss of habitat, but also to climate change and chemical pesticides. Mammals, too, are in trouble: In Australia especially, predators and fires are wiping out mammals at an alarming rate. And the mass extinction of insects is disconcerting – especially given their roles in key tasks such as soil processing, plant pollination, and decomposition.
When it comes to regions that were once home to extinct animals, North America leads the pack, followed by Oceania, Sub-Saharan Africa, and the Caribbean Islands.
Sub-Saharan Africa, South America, and Southeast Asia are most at risk for imminent loss of entire species. In Africa, many species are at risk due to threats including hunting and poaching, habitat loss, and illness.
South America is reeling from global warming. In Asia, people illegally trade at-risk animals for food or medicine. North America is a hub for species on the brink, such as coral reef, condors, marmots, and snails.
Animals with terrestrial habitats (on land) account for 65% of extinct species with a known habitat.
Past mass extinctions can mainly be attributed to natural occurrences: ecological transformations, natural climate changes, and interactions among animal species themselves.
But the reasons for this sixth mass extinction fall on our shoulders. Our surging human population has destroyed animal habitats through deforestation, urbanization, and overgrazing. We have polluted the planet, overhunted and overfished, introduced non-native species, and depleted wild plants.
The 20th century has thus far been the worst in recorded history when it comes to lost species. Of all the phyla, chordates have proven very vulnerable.
Chordates suffered the most losses of any phylum, due to various reasons: introduction of alien species, habitat destruction, and excessive fishing and hunting. Invasive species are the top threats to mollusks, and habitat destruction is the biggest threat to arthropods. Both worm phyla, with one extinct species apiece, count habitat destruction as the sole cause of demise.
Experts sometimes declare a species extinct, only to make a surprising discovery of a previously unknown population, a single animal, or even a recently deceased specimen. Though it is exciting and heartening, in most cases, these species are still endangered.
At a glance, the endangered and extinct animal crisis seems helpless. Heartbreaking. Infuriating. But if we work together, we can turn it around. You can spark change in your state, your city, your neighborhood, or even just your home. Find a single cause to get behind, and take baby steps:
- Tweak your diet.
- Change your mode of transportation.
- Lower your energy usage.
Ready to go further? Lobby for legislation, get behind conservation efforts, and sign petitions.
Efforts that signal hope for the future are already underway.
- Washington state residents voted overwhelmingly in favor of a bill to protect endangered species.
- Conservationists work to reduce artificial light on beaches during turtle nesting season to reduce deaths among disoriented hatchlings.
- North America’s black-footed ferret population dwindled to just seven in the 1980s but made a big comeback thanks to a breeding program.
We scraped EndangeredSpeciesInternational.org for its list of extinct animalia from 1500 to 2009. Extinction dates were grouped by century. Extinction cause was grouped into 11 categories based on the original extinction causes listed. These groupings can be viewed here.