Huge animals bend biological laws

The blue whale overcomes nature’s limitations by means of special adaptations such as a huge tail fin and an excellent ability to oxidize blood. The prehistoric fish lizard probably had similar characteristics.

WIDE HIND PART AND SLIM BODY CAUSE MAJOR PROPULSION

PROBLEM: Marine animals such as the blue whale and the extinct fish lizard move by means of flukes. The larger the animal, the more force is required to produce motion. If the animal keeps increasing its mass, it will be unable to move at some point.

SOLUTION: The blue whale's body is slimmer than the other whales', and its dorsal fins are very small. This reduces the resistance of the water. The fluke measures 7 m and makes sure to force the giant forwards at a speed of up to 30 km/h.

PROTEIN FORCES THE LUNGS TO WORK HARDER

PROBLEM: The more body mass an animal has, the more oxygen must it absorb to remain alive. The oxygen requirement is eight times larger, every time the aminal's size doubles, so the blue whale needs – and the fish lizard needed – huge quantities.

SOLUTION: A blue whale's lungs weigh 1 t each and can hold 2,500 l of air. Moreover, the whale can absorb 90 % of the oxygen of the air, as compared to 15 % for humans. This allows the marine animal to build a large store of oxygen in its muscles.

SEA MONSTERS SWALLOW PREY LIKE HUGE VACUUM CLEANERS

PROBLEM: An animal must eat according to its mass. This means that the food requirement increases eight times for every time the animal's size doubles. A blue whale must consume some 3.5 t of food a day to survive.

SOLUTION: Blue whales feed on krill, which can occur at a density of 770,000 individuals per m3 of ocean water. By opening its huge mouth inside a shoal of krill, the whale produces underpressure, so more than 2 t of krill flow into its mouth.

SOLUTION A 60-m-long blue whale needs an eight times bigger tail fin than a blue whale of 30 m to generate sufficient propulsion.

SOLUTION The fish lizard probably fed on large fish rather than krill. According to scientists, it also sucked its prey into its mouth.

SOLUTION A blue whale has twice as much haemoglobin in its blood as humans. The protein carries oxygen about the body.