Which Dinosaurs Roamed Delco?

Written by Pete Kennedy

Apropos of nothing, Patch decided to investigate which dinosaurs, if any, populated Pennsylvania during the Mesozoic Era.

Put another way—who might have been lumbering through your backyard 100 or 200 million years ago? For starters, there's Astrodon, the Maryland State Dinosaur, which is estimated to have been 30 feet high and 60 feet long.

According to paleontologist Jason Poole, the evidence of Pennsylvania's dinosaurs comes not from skeletal remains, but from fossilized footprints.

Poole is the Dinosaur Hall coordinator at the Academy of Natural Sciences of Drexel University in Philadelphia. He answered our questions via email (links have been added):

Patch: What dinosaurs, if any, roamed southeastern Pennsylvania in the Mesozoic Era? 

Poole: We have only footprint fossils from dinosaurs in Pa. However, dinosaurs like dilophosaurus, Astrododon, and various hadrosaurs, as well as many other genus did roam Pa. Our rocks are in general older than the dinosaurs, so we must look to other East-Coast states who have dinosaur aged rocks for the answer to this question.

What other interesting prehistoric creatures lived in this area? 

Again there are two questions here. What fossils are found in Pa. and what animals lived here.

We only find fossils from animals that lived in geologically depositional environment “flood plains and stream deposits,” places where new sediments are being deposited and bones are being buried. An area changes through time and will not remain depositional forever. Much of Pa. has been erosional for hundreds of millions of years. We do find Phytosaurs, fishes, and from some caves we find some cool “Ice-aged” animals.  

What types of fossils might residents in Delaware County find near their homes? 

There are many places in Pa. to find fossils like shells, trilobites [Pennsylvania's State Fossil], fern fossils, ancient crocodilians, and early fishes. It is extremely important to find out where it is legal to collect fossils. Collecting on federal or private lands without the proper permits and permissions can land a collector in more than a little trouble and on the hook for heavy fines.

The Academy of Natural Sciences of Drexel University is located at 1900 Benjamin Franklin Parkway in Philadelphia. It's open weekdays from 10 a.m. to 4:30 p.m., and weekends from 10 a.m. to 5 p.m. Admission is $15 for adults, $13 for children. For more information, visit the academy website or call 215-299-1000.