Are human beings considered mammals?
Yes, humans are mammals. But what is a mammal?
A mammal’s simplest and most common definition is “a warm-blooded animal that feeds its young with milk from mammary glands.” We’re all mammals because we feed our young with milk from mammary glands (we call this process breastfeeding), and we maintain our body temperature independently (otherwise known as endothermy). Mammals also usually have hair or fur made up of keratin, which is found in skin cells, claws, horns, and hooves. We, humans, share these traits!
We may not be hairy like some other mammals, such as cows or pigs, but we have hair follicles. We also have claws in our fingernails and toenails, just the hardened parts of the skin made up of keratin. Humans do not grow horns or hooves, but we share these traits with other mammals like rhinos and horses.
Mammals also have a neocortex region in the brain and often have three or more different bones in each ear.
These shared traits that define mammals make it so easy to classify species. Mammal classification is based on shared characteristics, so any organism with all or most of these traits can easily be classified as a mammal.
All these aspects mean that human beings are considered mammals.
What makes humans mammals?
Evolution teaches us that humans are closely related to primates, which are mammals. Mammals share key physical traits that set them apart from other non-mammal species. For example, we are also warm-blooded, so our bodies produce heat, unlike cold-blooded species such as reptiles.
The mammalian brain is a three-layered brain that shows great advancement from the brains of reptiles. Mammalian brains have a neocortex, basal ganglia, and limbic system. The neocortex is responsible for advanced thought and sensory information processing.
What makes humans unique from other mammals?
Humans are unique in that we have evolved to walk upright, which other mammals do not do. We also lose our body hair and produce less milk because of this. In addition, like other primates, we have opposable thumbs and five fingers, a rare characteristic.
In terms of DNA, the modern human has only a 1.2% difference in DNA from the chimpanzee and a 1.6% genetic gap with the gorilla.
However, we differ from other types of mammals in 3 key aspects:
- Our newborns are helpless at birth
- Our skin has a lesser microorganisms diversity
- Our brains have different ratios