Here is fascinating and captivating information about warm-blooded egg-laying birds. According to recent estimates, there are more than 10,500 species of birds on the planet. Scientists still haven’t determined exactly what species birds evolved from, but it is believed they descended from dinosaurs.
The Largest Bird in Ancient Times
The largest bird to have lived on Earth 5-8 million years ago was the mighty Argentavis. The remains of these giant birds were discovered in Argentina. It belongs to the order of falconiformes, as it anatomically resembles ancient storks. Its wingspan reached up to 8 meters, and its average weight was 77.5 kg. The length of the skull was 0.5 meters, and the humerus was 1 meter long.
Judging by the structure of its skull, hooked beak, and sharp talons, Argentavis was a predatory bird. Its prey was likely rodents, which it swallowed whole. Scientists believe it would track gatherings of small mammals and dive down with its massive wings to stun them.
The Largest Bird Today
The largest bird on Earth today is flightless – the African ostrich. It also has the largest eyes of any land animal, with a diameter of 5 cm. Scientists have found that the ostrich’s eyes are heavier than its brain. Additionally, these birds have enormous beak-mouths.

They also possess unique physical features: a stocky build, long neck, flat head, and straight beak. An adult ostrich can reach 2.7 meters in height and weigh up to 175 kg. These birds are also champions in running, with strong legs and horned toes. Their average running speed is 60-70 km/h.
Ostriches are omnivorous, feeding not only on plants but also insects, small rodents, and reptiles. As desert dwellers, they can go without water for long periods, though they will gladly drink and bathe when the opportunity arises.
Ostriches were once on the verge of extinction due to extensive hunting for their meat. However, farmers have saved them by breeding ostriches in captivity.
The Smallest Bird
The hummingbird is one of nature’s most extraordinary and smallest creatures. Their plumage is iridescent and colorful. The smallest of their kind, the bee hummingbird, is just 6 cm long from the tip of the beak to the tail, while the largest species grow up to 22 cm.

Hummingbirds make their nests from fur, spider webs, and small pieces of bark, hanging them on branches of bushes or trees. They lay two pea-sized eggs. There are about 350 species of hummingbirds, and their habitat extends across the Americas and tropical regions.
They feed on nectar from flowers. A hummingbird can flap its wings 78 times per second. They are the only birds on Earth capable of flying backward, made possible by their unique wing structure. It’s been found that their brains are the size of a rice grain.
The Most Dangerous Bird
The cassowary, a large flightless bird native to northern Australia, is considered the most dangerous bird in the world, as it occasionally kills humans. Its name comes from the bony casque on its head, resembling a helmet. In the Papuan language, “cassowary” means “horned head.” Their strong legs are equipped with sharp claws, and their middle toe has a 120 mm long, dagger-like claw.

Adult cassowaries can grow up to 1.5-2 meters tall, with an average weight of 60 kg. They can run through dense forests at speeds of up to 50 km/h and jump up to 1.5 meters high.
Interesting Facts About Birds
Each bird species has its own habitat and unique characteristics. They care for their chicks and spend much of their time searching for food. In the fall, birds migrate to warmer regions, following routes known only to them, and return in the spring.
Here are five more fascinating bird facts:
- There are flightless birds on Earth, such as the kiwi. Their vestigial wings, only about 5 cm long, are hidden beneath their feathers. They use them to tuck in their beaks. Kiwis also have no tails, but their feathers have a mushroom-like scent.
- The sharpest vision belongs to the hawk. It can spot a field mouse from 1 kilometer away and chase its prey through dense forests without crashing into trees.
- The most talented bird is the lyrebird, which is also beautiful. These birds spend up to four hours a day singing. They can mimic sounds of human technology (like a phone ringtone or chainsaw) and the calls of other animals (such as a dingo or koala).
- A giant bird once lived on Earth – the elephant bird, which went extinct 400 years ago. Based on eggshell fragments, its eggs were the size of seven ostrich eggs. Adult elephant birds weighed up to 450 kg.
- The most intelligent predatory bird is the New Caledonian crow. It crafts tools from available materials to help it gather food and keeps these “tools” for future use.
This is just a glimpse into the fascinating world of birds. There’s still so much more to discover on our planet!