'layer cake'.

...of sorts.
Walking with J each morning really is a glimpse into the minutia of the natural world.
She had carefully collected these bronze wing poos last evening and left them to dry on a tree stump. The curly wurly nature identifies them as from a bronze wing dove and apparently all bird poo is layered. The solidified lighter 'wee' at the bottom (without the grit obviously!) and the darker poo layer on top,

As a wildlife carer getting to grips (so to speak) with the poo structure is really important and can tell heaps about the health of the bird.  Too little of the lower layer perhaps the bird is dehydrated and too little of the top layer the bird may not have enough nourishment.
SO much to learn!!