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.
3. Sinus infection: Upper respiratory tract infections are usually associated with breathing and swallowing problems, which cause drooling due to accumulation of saliva. Also, when your nasal passage is blocked due to flu, you tend breathe with your mouth, which causes the excess saliva to flow out while sleeping. 4. Tonsillitis: Tonsillitis is the inflammation of glands called tonsils present at the back of your throat.