Premise | Research and Ideation 
Finally, I've found research specified to the 'conceptual' art of world-building. Looking towards visual styles in regards to the industry's existing responses to real-life guides to plants and animals, and Vandermeer's own aesthetics and themes, which in turn, will influence my concepts.
Annihilation has lots of links to the weird and uncanny; with humans attempting to pinpoint and 'clear up' the natural world at a time when nature is strongly revolting.
The main character is a biologist- and thus has a particular affirmation to the natural world she's exploring.
In regards to Bourne, the early stages of this revolt, prior to the events of 'The Southern Reach Trilogy'... We realise the link between nature and humans are more uncomfortably closer and more intertwined than initially thought. This animalistic aspect of humanity that cannot be controlled, and cannot be denied is a source of fear for many.
The protagonist is a scavenger. There's parallels to the idea of collecting life, and identifying life, but with Rachel her intentions are more streamline. If it doesn't help survival, it's not worth bothering with. Sentimentality and aesthetic preference is a luxury one cannot afford to survive.
The beginning features a pivotal moment of this change in outlook. For the first time in her scavenger life, she finds and collects a creature that has no obvious aid /worth to her survival.
This is an interesting cross to consider in regards to the visual world of 'Bourne' compared to 'Annihilation'.
Many existing 'animal guides' are there with the essence of curiousity, and wonder for the natural world. This relates to both the 'real-life' examples of the natural world (see post 2), and the ficticious ones.
I researched existing botanical studies/illustrative guides (see post 2) and an example of 'world building' with 'The World of The Dark Crystal' by Brian Froud, so to see the process I'd need to undertake to make my own 'Bestiary'.
The latter includes some lovely, characterful concepts that hold the distinctive essence of this world Froud had created. The variety, and abundant creativity has been a motivating source of inspiration for my own concept designs.