The correct answer is Soluble phosphorous
Soluble phosphorus is a measure of orthophosphate (PO4), the
soluble and inorganic filterable fraction of phosphorus, which is the most
stable type of phosphate and it is the form directly used up by the plant
cells.
Answer:the species could be seperated by many differnt barreirs like a storm that destroys a habitat and the species is split up but this does not mean that a new species would develop.
Explanation:
This is because the only reason new speices would develop is if when they get seperated the species move to a new environment forcing them to adapt.
There are more but birds would be a bad index fossils
I hope this helps!