Rare 150-Million-Year-Old Dinosaur Egg Nest Uncovered on Portugal's Santa Cruz Beach

Significant Paleontological Discovery in Torres Vedras

A remarkable discovery has been made on the cliffs of Santa Cruz beach in Torres Vedras, Portugal, with the unearthing of a nest containing approximately ten 150-million-year-old dinosaur eggs. The find, dating back to the Late Jurassic period, is considered a significant addition to Portugal's paleontological record and provides new insights into the reproductive habits of ancient dinosaurs.

The Discovery by Carlos Natário

The breakthrough belongs to Carlos Natário, a field researcher associated with the Society of Natural History of Torres Vedras (SHN) and the Center for Research in Paleobiology and Paleoecology (Ci2Paleo). Natário made the discovery while conducting routine prospecting and monitoring work on paleontological sites in the region. He spotted a peculiar outline in the weathered sandstone after a winter storm, which, upon careful clearing, revealed a tight circle of eggs embedded in the cliff face.

Characteristics of the Ancient Nest

The nest, found in sedimentary levels belonging to the Praia de Amoreira-Porto Novo Formation, is estimated to be from the Kimmeridgian stage of the Upper Jurassic. Researchers were particularly surprised by the small size of the nest and the granular sandstone in which it was found, a sediment type more typical of ancient riverbanks than beach dunes. This suggests the eggs may have been laid on a riverbank and possibly semi-buried. The eggs themselves are notably small, rarely exceeding five centimeters across, in contrast to most known Portuguese dinosaur eggs which measure eight to ten centimeters. Preliminary observations indicate that the eggs were arranged in an orderly manner, suggesting intentional placement rather than accumulation by water flow. Based on the general egg shape and shell porosity, experts believe they were laid by a small carnivorous dinosaur, possibly a theropod, small allosauroid, or even a *Eustreptospondylus*, *Torvosaurus*, or *Lourinhanosaurus*. Evidence suggests that almost all the dinosaur hatchlings successfully emerged from the eggs.

Scientific Importance and Future Research

This discovery is highly significant as only a handful of Upper Jurassic nests have ever been confirmed on the Iberian Peninsula, positioning Portugal as one of the few places globally where such finds occur. The site is considered one of Europe's richest windows into life approximately 150 million years ago. The fossil block has been transported to a climate-controlled laboratory in Torres Vedras. The next crucial step involves subjecting the eggs to high-resolution CT scans to create three-dimensional models of their interior. This non-destructive technique aims to determine if any preserved embryonic remains exist, which could potentially link the nest to a specific dinosaur genus. The discovery is also expected to bolster Portugal's 'Dino-Rota' (Dinosaur Route), enhancing its status as a key location for paleontological tourism and research.