Edmontosaurus annectens

Overview

Edmontosaurus annectens is a large herbivorous dinosaur with a broad, flattened beak. Fossils preserving skin and body outlines are studied alongside skulls. They reveal an outward appearance different from what the skeleton alone suggests.^[1][2]

Key facts

Bones alone do not reveal a dinosaur’s entire exterior. A 2025 study reported a fleshy ridge along the midline of the back and hoof structures. Soft-tissue traces renewed the appearance of a familiar dinosaur.^[2][3]

Time and place

It is associated with North America in the Maastrichtian at the end of the Late Cretaceous, roughly 72–66 million years ago. Head and body material from several fossil localities has been studied. It is a duck-billed dinosaur encountered in the final scenes of the dinosaur age.^[1]

The time range describes source context, not the complete duration of this species.

Size, form and skeleton

The adult skull is low and long, with an elongated front snout. A fleshy ridge along the back’s midline and projections on the hips and tail have also been studied. Hoof structures on three hind-foot toes have been reported.^[1][2]

Habitat and reproduction

It was a plant-eating hadrosaur. Comparing the broad beak, head, and supporting feet helps us consider herbivorous dinosaur life. This species has also been proposed as the most likely owner of healed tail vertebrae with a Tyrannosaurus tooth embedded in them.^[1][4]

Fossil discovery

A 2011 study compared skull growth with differences between species. In 2025, research analyzing soft tissues and hooves in mummy fossils was published. Even long-known dinosaurs continue to change in appearance through new specimens and observation methods.^[1][2][3]

References

1. Campione & Evans2011 — Cranial growth and variation in Edmontosaurus
2. Sereno et al.2025 — Fleshy ridge and hooves of a duck-billed dinosaur
3. University of Chicago2025 — External body appearance revealed by dinosaur mummies
4. DePalma et al.2013 — Evidence of predatory behavior in Tyrannosaurus
5. Prieto-Márquez & Salinas2010 — Secernosaurus and South American hadrosaurs
6. McClung Museum Edmontosaurus

Research questions

How much did juvenile and adult heads differ? Growth-related features must be compared alongside differences between species. Adding skin and soft-tissue fossils allows investigation of the relationship between skeleton and living appearance.^[1][2]

Observation

Move your gaze from the broad beak through the neck, back, and trunk to the feet. Consider what skulls, skin, and hooves each reveal about appearance.^[1][2]