Here's a breakdown of what "Mammalia" signifies:
* Class: This is a taxonomic rank in the biological classification system, placing mammals within a broader group of animals called vertebrates.
* Mammary glands: This unique feature distinguishes mammals from other animals and is crucial for their reproductive success.
* Milk: This nutrient-rich substance provides essential nourishment for developing young, allowing for longer periods of parental care and greater survival rates.
So, "Mammalia" encompasses all animals that share the common trait of having mammary glands and producing milk for their offspring.