In the past, Hollywood has made a lot of movies about dinosaurs. Especially about dinosaurs living far from the hills of Hollywood. But did you know that 75 million years ago armored dinosaurs once roamed the hills and flatlands where today’s Hollywood tourists now roam? Along with the armored dinosaurs, known as Aletopeltas, saber-tooth tigers hunted their prey in the same area 2.5 million to 10,000 years ago. While dire wolves competed for the same food sources 125,000 to 9,500 years ago.

Aletopelta is a genus of ankylosaurid dinosaurs that lived in Southern California about 75.5-million-years ago. It is the only dinosaur ever to be found in southern California, and one of the few dinosaurs to be found in the entire state. The name Aletopelta means “wanderer shield,” because it was carried northward by plate tectonics from its original location near Mexico. Aletopelta was about 16 feet long and weighed about 2 tons (4,409 lbs.). It had a bony tail club and a pelvic shield made of osteoderms, which are bony plates embedded in the skin.

Ankylosaurus was a plant-eating dinosaur that was the largest of its family of dinosaurs called ankylosaurs. This family of dinosaurs had short, heavy bodies and were protected from head to tail with bony plates and spikes. The plates acted like armor, to help protect the animal against meat-eating dinosaurs (carnivores).

Aletopelta was discovered completely by accident in 1987; a road crew was doing construction work near Carlsbad, (115 miles south of Los Angeles) and the fossil of an Aletopelta was recovered from a ditch that had been excavated for a sewer pipe.

The Saber-Tooth Tiger is far and away the most famous (and most common) prehistoric mammal of California. This is known thanks to the recovery of literally thousands of complete skeletons from the famous La Brea Tar Pits of downtown Los Angeles. This predator was smart, but clearly not quite smart enough, as entire packs of saber-tooths got trapped in the muck when they attempted to feast on already-mired prey.

The saber-tooth tiger had a pair of elongated canine teeth in its upper jaw that were over 7 inches in length. These teeth were probably used for stabbing and slashing prey, such as bison, horses, mastodons, and ground sloths. The saber-tooth tiger was not closely related to the modern tiger or other modern cats. These ancient animals could weigh up to 880 pounds and had a muscular body and short limbs.

The dire wolf, Aenocyon dirus, is an extinct canine that lived in North America and eastern Asia 125,000 to 9,500 years ago. It was about the same size as the largest modern gray wolves, but had a more massive skull, a smaller brain, and relatively light limbs. It was a different species from the modern gray wolf. It is probably the most common mammal species to be found in Los Angeles’s famous La Brea Tar Pits.

Off the coast of Santa Monica, California—which is next door to Hollywood—lurked one of the largest and most powerful predators to have ever lived. It was the 67 foot long, 228,000-pound megalodon, an extinct species of shark. It had a massive skull with enormous jaws and giant teeth that could grow to over 7 inches. These teeth were used for stabbing and slashing prey, such as whales, seals, dolphins, fish, and other sharks. Megalodon fossils have been located in shallow coastal areas around the world, excluding Antarctica.

In 1980, Cuban-born physicist Luis Alvarez — along with his physicist son, Walter, concluded that the Earth was struck 65 million years ago by an iridium-rich meteorite or comet (the Chicxulub comet). The iridium residue from the impact object, along with millions of tons of debris from the impact crater, would have quickly spread all over the globe; the massive amounts of dust blotted out the sun, and thus killed the vegetation eaten by herbivorous dinosaurs, and this led to the demise of the carnivores.

A global catastrophe occurred 250 million years ago, resulting in the extinction of most land and marine animals. Ironically, it was this extinction that cleared the field for the rise of the dinosaurs—after which they managed to hold the world stage for a whopping 150 million years, until that unfortunate visit from the Chicxulub comet.

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