Your dog doesn't need to drink orange juice. There are evolutionary and biochemical reasons why humans need to consume vitamin C but dogs -- and many other animals -- do not.
A study of the dietary preferences of dogs and cats show distinct differences when palatability is constant. Are there lessons for us about our eating choices?
Evidence indicates that dogs can become infected with human-adapted influenza strains, making this incredibly concerning. When two different influenza strains infect the same host, the viruses can swap genes, a process known as genetic reassortment. This can produce devastating influenza pandemics.
The relative size of the human male's penis and testes can be reduced to our species' mating strategies, and can provide some surprising insights into early human culture.