One of the most frequently asked questions about manatees concerns their categorial membership; in other words, people often find themselves wonder...

One of the most frequently asked questions about manatees concerns their categorial membership; in other words, people often find themselves wondering if manatees are mammals or fish. 

Manatees are, in fact, mammals. 

However, the fact that so many people feel a need to inquire as to whether manatees are mammals indicates something about their status within this category. What exactly would this be, and what is probably the main reason behind it? 

a.

It indicates that manatees are peripheral members of the category MAMMAL, probably because, unlike most mammals, they are aquatic.

b.

It indicates that manatees are actually not mammals but belong to a different category altogether, probably because they do not meet the official criteria for membership within the first category. 

c.

It indicates that manatees are a type of hybrid creature, probably because they have peculiar mating habits. 

d.

It indicates that manatees are not well-known creatures, and people are unsure about their basic characteristics, probably because they are difficult animals to observe. 

e.

It indicates that manatees are perceived by most people as central members of the category FISH, probably because they are aquatic animals.