Plantosaurus Rex Prehistoric Plants at the Conservatory of Flowers

May - October 2012

Step back in time … WAY back in time as the Conservatory of Flowers transports you to a real life land of the lost in its newest exhibition Plantosaurus Rex. It's a prehistoric paradise of plants from the time of the dinosaurs when giant ferns, spiky horsetails, and primitive cycads grew in lush abundance and fed many of the monstrous reptiles that roamed the earth millions of years ago. Under a canopy of primordial conifers, visitors encounter model dinosaurs like the armored Stegosaurus foraging for the vegetation they loved best while learning about the symbiotic relationship between ancient flora and fauna. But beware — the predators have come to Golden Gate Park too! A giant T. rex has smashed through the roof of the Conservatory to look for potential snacks!

Inside the exhibition, a path through the past takes the curious on a fascinating journey along the timeline of plant evolution during the Mesozoic Era (approx. 250 – 65 million years ago) as the arid and barren supercontinent Panagaea broke up into the multiple continents we know today, bringing more water and humidity inland and giving rise to an explosion of plant and animal life.

The exhibition begins in the Triassic Period, the first of the Mesozoic Era's three periods, dating from approx. 250 to 205 million years ago. Both the start and end of the period were marked by major extinction events, but in between life on earth began to change dramatically. In the earliest part of the Triassic, plant life clung to the shores of Pangaea, surviving the hot, dry climate by sticking close to the water. Visitors are introduced to some of the major plant groups of the day including ferns, cycads, and lycopods (club mosses).

Animals depended on this sparse vegetation to rebound from the devastating extinction. Insect populations began to recover including many giant varieties, which persisted from the earlier Permian Period like the predatory Meganeura, a massive dragonfly-like creature with a wingspan of over 2 feet. Visitors encounter a model of one of these monster bugs in this area of the exhibition, coming face to face with the biggest insect that ever lived.

The Jurassic Period (approx. 206 to 144 million years ago), also known as the "Age of Reptiles," was the heyday of the dinosaurs, and plants made life possible for these gargantuan reptiles. During the Jurassic, the great supercontinent Panagaea experienced a major rift and split in two. All of this newly formed coastline, coupled with a warmer, wetter climate that gave rise to inland seas and lakes, created the perfect environment for plants to thrive. The dominant land plant species of the time were non-flowering, fruitless seed plants including Gingko and conifers like Araucaria along with another important dinosaur food, horsetails. Here visitors meet one of the great herbivores of the dinosaur world, an impressive 7-foot long baby Stegosaurus, back bristling with armored plates and head low to the ground to munch on favorite plants. Visitors also encounter one of the most notorious carnivores of the Jurassic, the bipedal Allosaurus, an efficient killer with a massive skull, plenty of sharp teeth, small, slashing claws, and a long tail.

The third and final section of the exhibition takes visitors into the Cretaceous Period (approx. 144 – 65 million years ago) to experience one of the most defining moments of plant evolution, the emergence of flowering plants. It was about 140 million years ago that the first flowers appeared, and soon they would dominate the landscape. It was a vibrant and accelerated world, and some of its pioneers included orchids, water lilies, and magnolias, all featured in the exhibition.

Dinosaurs benefited from this veritable vegetative feast and continued to evolve during this period. More of them took wing like the pterodactyl. Visitors can see one of these impressive creatures soaring overhead. Predatory dinosaurs were on the rise as well, including the most famous of all, the Tyrannosaurus rex. The great 'tyrant lizard king' was the largest carnivore in its environment, weighing more than 7 tons on average. In fact, the Conservatory's 23-foot tall T. rex will be the first thing visitors see on their approach to the famed old greenhouse, its head bursting through the roof of the building to look out over Golden Gate Park for "potential prey."

If visitors avoid T. rex's gaze and actually make it to the door, they will all receive a free booklet guide with paid admission to help them navigate this fascinating evolution of prehistoric plants complete with exhibit activity suggestions for young paleontologists. Docents will also regularly be on hand to share fossil specimens and answer questions.

The Conservatory of Flowers would like to thank the following media sponsors for their support of the exhibition: