In biology, or really most sciences (math being an exception), the more closely you examine a delineated this or that categorization, the more you realize it's a scale, a range, or something fuzzy.
Like even things we talk about regularly like touch and space is vague in the details. Is it still touching if the repulsive force of electron to electron is keeping nucleus apart? Where is empty space begin and an atom end? Is it after the electron shell? Outside of it's repulsive force? Some hybrid value?
I can always be awestruckdumb by the understanding that we are all mostly space inhabited by fields, our littlest bits vibrating at mindblowing speeds.
Like even things we talk about regularly like touch and space is vague in the details. Is it still touching if the repulsive force of electron to electron is keeping nucleus apart? Where is empty space begin and an atom end? Is it after the electron shell? Outside of it's repulsive force? Some hybrid value?