I slipped and wrote "higher eukaryotes" in relation to yeast and this is my post-doc's comments:

"that broke my heart :( other eukaryotes? multicellular eukaryotes? animals? Whatever you like, but please, no "higher", the poor yeast have been evolving for a long time and are much better than us at fermenting beers..."

<edit> This is a great paper that touches on animal complexity, see "Developmental Depth" and "Structural depth" https://www.researchgate.net/publication/228365097_Possible_...

Complexity, as in complexity of gestation, development and life cycle.

What units are used to measure complexity?

Based on how many grams of weed it has smoked.