Same reason humans' hair changes color when they get older.
They were older humans who traveled to Different places to live.
Yes..
Yes, like humans, a dog's voice/bark will get deeper when they get older
calicivirus is a desease only a cat can get, usally kittens or older cats. humans cannot get it
Tumor
Dogs are older than human because they leave longer than any other creatures
they grow s they get older sort of the same way humans do
yes, they get older just like humans
people have only been around for about 500,000 years... I say Cats are Elder to Human Beings
as the body's systems get older, they require more blood flow to operate, thus causing increased heart rate
Yes. As a stream gets older and older it's strength and speed reduces (like in humans). So, erosion is reduced.