What is the Fastest Animal in the World?

The fastest human alive, Usain Bolt, holds the world record for 100-metres with a time of 9.58 seconds. Bolt has the ideal traits for high speeds:

• Tall height
• Balanced weight
• Powerful muscles

But even though Bolt rules the roost among us humans, his top speed of 27mph is a slow jog for the fastest animals on Earth.

The worlds fastest animals are the pinnacle of millions of years of evolution. In the arms race of hunter and hunted, speed can be a weapon for both offense and defence. All of the world's fastest animals are exquisitely adapted for high speed movement - with some risking life and limb to go faster.

In a race between the Peregrine Falcon and the Cheetah, the bird would pass the cat in a matter of seconds and then disappear over the horizon. The Falcon can hit an enormous 200mph (320kph) at the bottom of a dive (stoop) making it the fastest animal on the planet.

This colossal top speed is achieved with a helping hand from gravity. The Peregrine starts a hunt by climbing to a great height and then diving on its prey - even when they themselves are airborne (the staple food of a Peregrine is the humble pigeon). The effect of gravity is maximised by the Peregrine's anatomy:

• An enlarged keel allows for a greater number of bigger muscles to attach the wings to the body. This allows it to build a huge amount of power per thrust to build up speed.
• Streamlined and ultra pointed wings combined with stiff and unslotted feathers significantly reduces air resistance and maximises acceleration and speed.
• The Peregrine maintains a steady oxygen flow from its (enlarged) heart and lungs to its (numerous) red muscle fibres. Consequently, the Peregrine does not suffer from oxygen deprivation and does not need to rest post-kill.

0-60 in three seconds, the acceleration of the Cheetah rivals that of the most technologically advanced supercar. Cheetahs have dedicated themselves to life in the fast lane with a top speed of 70mph. This high speed and vicious acceleration come at a price - the Cheetah risks brain damage and starvation due to the huge demands high speed places on their anatomy.

Cheetahs have a number of adaptations to maintain their top speed:

• Enlarged lungs and nostrils allow for a fast and deep air-intake. Breath-rate increases three-fold during a chase
• For its body size, Cheetah have an enlarged heart to pump a huge amount of blood around the body during a chase
• A flexible spine acts a spring, increasing the top speed. This high speed is counterbalanced with a long and flexible tail. This is the key to the Cheetah's agility.
• The Cheetah is the only big cat that cannot retract it's claws - this maximises grip on the dusty plains.
• Like all supercars, the Cheetah is lightweight - with a slender build (to minimise air resistance) and average weight of 125lb (57kg), the Cheetah has an outstanding power-to-weight ratio

Despite these adaptations, the Cheetah can only maintain a sprint for a matter of seconds; a long chase leaves a Cheetah dangerously close to oxygen deprivation (this is why Cheetahs try to close the gap as much as possible before starting a chase). To compensate for this a Cheetah must rest post-kill before it eats, this leaves plenty of time for Hyena and Lion to steal the kill.

The Sailfish has a top speed matching that of the Cheetah - 70mph. The sailfish can flick its tail back and forth hundreds of times during a chase to consume fish or squid. The top speed is maximised with a stiffened, tapered body and a large, retractable dorsal fin to reduce the effects of drag. A flexible spine also allows the sailfish to generate increased thrust through the rapid curves it bends its torso into during a chase.

The speediest insect on our planet is the Tiger beetle - a fast and agile predator common to brownfield sites. With large eyes and huge mandibles, it is clear that this beetle is a hunter. Unusually for insects, the tiger beetle is as fast on the wing as it is on foot - with reaction times comparable to the house fly (widely considered one of the fastest reacting animal on the planet). Whilst a top speed of 5.6mph (8.4kph) may not seem fast, compared to body length these animals are around 22 times faster than humans.