After every expedition, you can get supply boxes apart from the dinosaurs captured. Inside these boxes, you will be able to find amber and ammonites, as well as excavation tools and map fragments. The map fragments (you can see the icon right below the gems counter) will allow you to keep opening new excavation levels, so we recommend you send expeditions regularly to all your habitats. Have a look at the lab to unlock the research related to supply boxes in all the habitats.