He estimated how many species of insects lived on each plant species in England, and then extrapolated that figure across the whole planet. âIf we say 400,000, we shall, perhaps, not be very wide of the truth,â he wrote. Today, scientists know the Westwood figure is far too low.
Symptoms: A chronic dry cough that's worse at night, disturbing sleep, and sometimes with wheezing and shortness of breath. Causes: An irritating night cough is often the first sign of asthma, especially in children, but you can develop it at any age. It's also a sign asthma is worsening or not being well controlled.
A dry hacking cough is a type of nonproductive cough that is most commonly caused by smoking, asthma, allergies, bronchitis, and colds. People who smoke can sometimes develop a chronic dry cough because of irritants in cigarettes. Some illnesses, such as a cold or bronchitis, can also bring on a this type of cough.