Corals are small colourful marine animals that are found in the seas. They build the coral reefs. Their exoskeletons provide the structure of the reefs. The reefs are of high ecological importance. Corals grow very slowly at the rate of about one centimetre a year.
Case moth caterpillars (Psychidae) make a case around them, which is made of silk and pieces of plants or soil. Female case moths complete their entire life cycle in their case. When female case moths grow old, they lay eggs in the case. They then crawl out of the case and die. Their progeny are…
In 1862, Charles Darwin discovered an orchid from Madagascar with a one-foot-long spur that held the pollen and the nectar at its depths. He predicted that there must be an insect that had a foot long tongue (proboscis) to pollinate the plant. Nobody had seen such a moth and the idea was laughed at. In 1903,…
Butterflies are delicate creatures and they are affected by climate change. A large population of butterflies indicates a healthy ecosystem and a dearth of butterflies indicates that the ecosystem is under stress. Butterflies are unable to fly if their body temperatures drop below 30 degrees Celcius.
An average hurricane bringing in 1.5 cm per day of rain, with a circle radius of 665 km, generates a huge amount of energy (6.0 × 1014 Watts or 5.2 × 1019 Joules/ day), which is equivalent of 200 times the electricity-generating capacity of the entire planet in a year. This is equivalent to detonating…
A raindrop falls on the earth with varying speeds depending on its size and weight. The gravity acts on the falling raindrop and the drop picks up speed. But due to air resistance, which is generally proportional to the velocity, the raindrops attain a terminal speed. A larger raindrop would fall much faster at 9…
