Running speed
The first President of the U.S. George Washington, was sworn in as President in 1789. The U.S. has had 46 Presidents so far. But none of them were women! Here, India has the trump card. Of the 15 Presidents so far, two have been women: Pratibha Patil (20072012) and Draupadi Murmu (current President). Even when we look at our immediate neighbours, we have had women heading important offices. Benazir Bhutto was the Prime Minister of Pakistan, Sheikh Hasina is the current Prime Minister of Bangladesh, Bidya Devi Bhandari was the second President of Nepal, and Dolma Gyari was the woman Prime Minister of Tibet between 19912011. And several ‘developing countries’ in Latin America have had women Presidents and Prime Ministers.
Let us thus have happy women’s days and years.
Why do medium-sized land animals like cheetahs tend to be the fastest?
While many key traits such as strength, limb length, lifespan and brain size tend to increase with animals’ size, maximum running speeds tend to be greatest in mediumsized animals. Empirical data show that maximum running speed increases up to a critical body mass and then decreases — the fastest runners are of intermediate size. The findings suggest that there is not one limit to maximum running speed, as previously thought, but two: how fast versus by how far, muscles contract.
The maximum speed an animal can reach is determined by whichever limit is reached first — and that limit is dictated by an animal’s size. The maximum running speed is constrained both by how fast muscles contract, as well as by how much they can shorten during a contraction. Animals about the size of a cheetah exist in a physical sweet spot at around 50kg, where these two limits coincide. These animals are consequently the fastest.