Quick answer
Dr. Ivy’s egg route requires a complete fossil set. Finish the set before you head to the DNA Lab; no universal piece count is confirmed in the public game description.
On this page
Check completion before the trip
Use the current in-game set display to compare collected and missing parts. This is a general collection check, not a claim that the game uses a particular inventory tab.
The conversion destination
Bring the full set to Dr. Ivy at the DNA Lab to grow an egg. Incubation is the next task, after the fossil-to-egg conversion.
Keep species and quantities separate
A set list needs actual item names and required counts. This page explains the full-set prerequisite without inventing a recipe for an unverified species.
Your next task
Choose the guide that matches the step you are working on next.