So adapted are dogs to smelling the outside world that they have little ability to smell food in their mouths. When humans chew food, we force gases escaping from the food up into our nasal cavity via passageways in the back of the throat. This process, called retronasal olfaction, partially reverses the flow of air in the nose, which normally comes in through the nostrils. [...] But the internal anatomy of a dog’s head allows little of this backward airflow. Dogs mostly lack the combined feeling of smell and taste that makes up flavor. As a result, they care little about the flavor of their food once it is in their mouths. Detecting the smells of edible things before opening their mouths is enough for them to take a bite.

— Read more in Do Dogs “See” Smells? at Psychology Today.

Humans have about five million scent cells, while wolves have 200 million. The olfactory center in a human’s brain is the size of a pea, while a wolf’s is the size of a fist. Wolves can smell other animals from more than a mile away, using pheromones to gather information about that animal. A wolf can recognize a member of their pack just by scent. Their specialized scent glands are as unique as a human’s fingerprint.

— Read more in What makes sense to a wolf at Pikes Peak Courier.

However, even after knocking out an entire family of odor-sensing receptors from the mosquito genome, mosquitoes still find a way to bite us. Now, a group of researchers, publishing in the journal Cell on August 18, found that mosquitoes have evolved redundant fail-safes in their olfactory system that make sure they can always smell our scents.

— Read more in Mosquitoes have neuronal fail-safes to make sure they can always smell humans at Science Daily.