Why do our stomachs grumble? Because the muscles in the stomach and small intestines are contracting and there is no food in there to muffle the sound. Our stomachs rumble a lot of the time, but we usually cannot hear it because the food in our stomachs and small intestines soak up the sound. The […]
#429 Why do our stomachs grumble? Read More »
How do mammals keep warm in the winter? They have several different methods. Here are some of them. Many mammals stay warm by putting on more fat. Sea mammals have to cope with very cold ocean water and it is harder to stay warm in water than it is on land. If you are naked
#424 How do mammals keep warm in the winter? Read More »
Why do fish have scales? For protection, for camouflage, and to help them swim faster. There are four basic types of fish scale, but there are many subdivisions within each category. These are the main ones: Placoid scales. They are found on fish such as sharks and manta rays. They are very similar to teeth,
#414 Why do fish have scales? Read More »
How do fish breathe underwater? Fish use their gills to take oxygen out of the water. Why do we need oxygen? Most living beings need oxygen to create energy. All animals need to respire, which is the process of releasing energy by breaking down glucose. There are two ways to respire: aerobic and anaerobic. Aerobic
#412 How do fish breathe underwater? Read More »
Why don’t cats knock things over? It turns out that cats have whiskers on their legs as well as their faces. When I’m making a line of dominos with my daughter, it is inevitable that either she or I will knock them all over. We both seem to have no sensory perception. And yet, my
#411 Why don’t cats knock things over? Read More »
Do ants need to sleep? Ants do actually sleep, but not all at once. There are very few living organisms that don’t need to sleep. However, they all do it in different ways and there are many different definitions of what sleep is. Bacteria don’t sleep. Although they are tied to a circadian rhythm and
#405 Do ants need to sleep? Read More »
Why are rabbit ears so long? A rabbit has big ears to cool itself down, not just to hear predators. Rabbits are herbivores and are obviously preyed upon by various other animals. Their large ears can swivel independently and can pick up sounds from up to 3km away. They can turn each ear 270 degrees,
#395 Why are rabbit ears so long? Read More »
Why do mosquito bites itch? Mosquito and insect bites itch because the immune response is triggered after the mosquito finishes biting. There are over 110 trillion mosquitoes from 3,000 different species around the world. I have no idea how they managed to calculate the number of actual mosquitoes. The word “mosquito” comes from Spanish where
#385 Why do mosquito bites itch? Read More »
Why does a chicken’s head stay perfectly still when you move its body around? Because chickens cannot move their eyeballs in their eye socket and because they don’t have a vestibulo-ocular reflex. Our heads (humans) are pretty much constantly moving, yet we can see perfectly well. This is all thanks to the vestibulo-ocular reflex which
#374 Why does a chicken’s head stay perfectly still when you move its body around? Read More »
When did the last woolly mammoth disappear? A population of woolly mammoths survived on Wrangel Island until about 2000 BC, about 500 years after the Great Pyramid of Giza was built. Woolly mammoths appeared in Siberia about 700,000 years ago. They were the same size as a modern African Elephant: up to 3.4 m at
#371 When did the last woolly mammoth disappear? Read More »
