I was wondering the same thing. But as pointed out here[1]. There are some interesting points: Cell size is actually affected to genome size and cell size has

I was wondering the same thing. But as pointed out here[1]. There are some interesting points: Cell size is actually affected to genome size and cell size has a more complex relation to Physical Shapes and sizes: " As a result, species that are the same physical size but have different genome and cell sizes likely also differ in ways that significantly affect morphogenesis, growth, and adult morphology. Analysis of organismal size and size change thus becomes a consideration not simply of physical size, but also of a more elusive concept-biological size." Even within a species the variation is tremendous: "In some groups, miniaturization may have been achieved by cell size decrease (65). In others, extensive genome and cell size variation complicates tremendously even basic comparisons of body size among taxa." I remember seeing attenborough on TV how a species of frogs living in the cold areas just allow themselves to be frozen for long periods of time and then thaw back to life! [1] https://www.researchgate.net/profile/James_Hanken/publication/290469788_Miniaturization_of_Body_Size_Organismal_Consequences_and_Evolutionary_Significance/links/56f28c0f08ae4cb04b2647a0/Miniaturization-of-Body-Size-Organismal-Consequences-and-Evolutionary-Significance.pdf https://www.researchgate.net/profile/James_Hanken/publicatio...