This unit is definitely one of the most information crammed units in the book. Many students are scared they won’t be able to memorize the hundreds of scientific names present. If I could say just one thing about the unit, it’d be, STOP WORRYING!

If you’ve looked at USABO cutoffs for Open and Semis, none of them have ever been 100% or even close. Accordingly, you don’t need to be perfect. USABO is about exploring your passion for biology, so do exactly that. If you find diversity stressful, then study the units you like better! I personally think identifying flowers and bugs is kind of fun, but many, more sane people do not. This advice applies to basically every unit of the book. Study what you’re interested in! You’ll learn more efficiently and carry more of the material with you to the competition.

That being said, here are some tips for this unit. If you want to learn just the most important tidbits, check out chapters 26-27 and 29-32. Chapter 26 is pretty darn important for systematics concepts. Make sure you understand all the tree-related terms (phylogenetic tree, not tree tree). In Chapter 27, make sure to understand the general characteristics of bacteria, though whether you want to know the specific bacterial groups is up to you. In Chapters 29-30, make sure you know the life cycles and terminology as much of it comes back in the actual plant unit. In Chapter 31, know the general characteristics of fungi and the various life cycles. And finally, in Chapter 32, learn the basics of animal development and morphology. For example, know what a coelom is and which animals have one, don’t have one, or have a fake one.

As for the other material in the unit, as I said, study if if you enjoy it, but otherwise, don’t worry.