The Natural History Museum of Los Angeles County is located at 900 Exposition Blvd. in Los Angeles. Museum hours are M – F 9:30 AM to 5 PM and S – S 10:00 AM to 5 PM. Information is available at (213) 763-DINO and on the museum’s web page at www.nhm.org. Admission is $5.50 for students (with ID) as of Spring 2002. Parking is $5.00.

Plan at least a two to three hour visit to the museum, and carefully fill in the blanks to answer the questions as indicated. Staple your ticket stub to this page before turning in the assignment.

There are two large dinosaur skeletons mounted in the Rotunda. They are the same dinosaurs that you saw life-sized models of outside the museum on Exposition Blvd. They are two of the most famous dinosaurs, Triceratops and Tyrannosaurus. These fossils were found in rocks from what geological era and period?

Era ____________________________ Period __________________________________  HINT:  You will find a map in the first room of the Dinosaur Wing.  The map is occasionally moved around.

Look carefully at the skeleton of T. rex. How many fingers does it have on each hand (called the manus)? Toes on each foot (called the pes)?

Note that it has numerous holes in the lower jaw and skull. What advantage might these have had for this large animal?

Triceratops and Tyrannosaurus are representatives of the two major groups of dinosaurs. In the boxes below are diagrams of the two pelvises for these animals. Identify which each belongs to.                                                                                                        _____________________________

______________________________

Saurischia Ornithischia

Between the Rotunda and the dinosaur hall you will find a case containing a Coelacanth. This fish, caught off Madagascar, was once thought to have become extinct when the non-avian dinosaurs died out some 65 Million years ago Use the information in and on this case to answer the following questions.

What is its scientific name?

Where and when was it found?

Look at the pectoral girdle (shoulder) and pelvic girdle (pelvis) fins. How are they connected to the body of the fish that is different from the fish you are familiar with?

This is a member of the lobe-finned fish. They are noted for a bone arrangement in the limb connecting their fins to their respective girdles. That arrangement is to have on bone attached to the girdle, the upper limb, a hinge joint, and then two bones connected to the fins, the lower limb, and then a rotational joint. What advantage could such an arrangement provide?

What other animals share this limb bone arrangement?

All animals sharing a common ancestor with the lobed-finned fish are called Tetrapods (4 limbs). Are we a tetrapod?

A more visible shared feature would be the presence of five digits on each hand and foot. Be looking for this in later exhibits.

Turning to your right you will approach the Dinosaur Hall. Just before entering that Hall you will pass a large display case on the left. Inside are many different forms of body fossils, trace fossils and pseudo fossils.

List three ways in which fossils are preserved other than petrification.

List the names of at least two pseudo fossils.

List the names of at least two trace fossils.

Enter the first room of the Dinosaur Hall. None of the animals found in this room are dinosaurs. They are reptiles or invertebrates. How to tell the difference? One way is to look at the skull. In dinosaurs and pterosaurs, flying reptiles, there are two openings in the skull behind the eye socket. This is referred to as a Diapsid condition. Early reptiles and mammals have only one opening, called Synapsid, while amphibians and turtles have no opening, or Anapsid. This differentiation is the basis for the Subclasses of Reptiles, the Subclass Anapsida, the Subclass Synapsida, and the Subclass Diapsida.

First lets look at the marine reptiles. What are their common and scientific names?

What features do they show that indicates they are aquatic?

Many times fossil have fascinating stories to tell. There are two such examples in this room. Note the Pterosaur that is mounted against the east wall – YES as geology students you should be able to tell direction indoors. This is obviously a flying reptile. What portion of its forelimb is used to support its wings? What part do its fingers play? How many fingers does it have?

Looking at its teeth, what type of food do you think it ate? Think about modern birds that you have seen with a skull this shape.

Look at its neck, about 3 vertebrae down from the skull. Do you see the shark’s tooth embedded there? We know that this skeleton was found in terrestrial deposits, land. We know that the skeleton was intact, it had not been broken apart by a meat eater. Now what story can you put together to fit the above facts about the last few minutes of its life?

Turning to your right you will see in a wall display case a large clam. Inoceramus is the general name for these clams. What is the common and scientific name for this particular specimen?

Modern giant clams live upright with their hinge buried in the sediment. They live for a number of years. What would you expect to find on this specimen to indicate that it had the same habit as a modern giant clam? Do you find it?

We can even tell when this clam died, day or nighttime. How? See if you can find information on the internet about modern giant clams and their association with small fish. Does that help????

In this room, they keep moving it around, is a map of North America during the time of the dinosaurs. What does it show occupying the interior of our continent?

Entering the next room you are greeted with several complete mounted skeletons of dinosaurs and some that are not dinosaurs. Most of these are not real, that is they are made of casts made from the real bones. We do not have many specimens of complete skeletons from many of the animals you will find in these displays. Therefore, making casts is one way of allowing many museums to have displays of the various animals. Frequently the skeletons shown are not even complete. In that case the missing parts will be modeled and be in a different color material.

Find the skeleton of Morenosaurus. What was the habitat for this animal, and what is the evidence from the skeleton that tells you about that habitat?

From the teeth you can tell that it ate?

What type of animal was Tylosaurus?

Find Dimetrodon. He is noted for the large sail on his back. From the information provided, what are the possible uses of this sail?

The animal called Postsuchus is not a dinosaur. Look at the bones in the feet, and compare them with Carnotosaurus, which is a true dinosaur. What differences do you see?

A full size replica of a nest of dinosaur eggs is on display. In the space below, draw on of the eggs, paying particular attention to the shape of the egg.

How does the shape of this egg compare with that of a chicken?

What does this suggest about dinosaur behavior around the nest?

These are amniotic eggs, like a bird's egg but not like an amphibian's egg.  This change from the amphibian egg which must stay in water is what allowed the reptiles to populate the land, straying from the waters edge.  The advantage comes from the covering of the egg, the egg shell, which protects the egg from drying out.  If this egg is isolated from the atmosphere, except for the passage of gasses like oxygen and carbon dioxide, what must it contain for the embryo to survive?  HINT: think of a space ship.

You can’t miss the skeleton of Mammenchiasaurus. To what group of dinosaurs did this animal belong?

Note the long calcified cartilage struts along the bottom of its neck. What do these suggest about the "standard" model of these large sauropods stand with their neck arched in an S-shape?

What feeding strategy did this animal employ?

Find the skeleton of Allosaurus. How many fingers did it have?

What is its feeding strategy?

Both Allosaurus and Mammenchiasaurus lived during the _____________ era?

Look at the dinosaurs in this room. Below write the names of each that are

Bipedal and herbivore

Bipedal and carnivore

Quadrupedal and herbivore

Quadrupedal and carnivore

Examine the skeleton of Edmontosaurus. Examine the teeth closely. These teeth were modified for chewing what type of food?

Compare the skeleton of Edmontosaurus to the skeleton of Morenosaurus, Corythosaurus and Dilophosaurus. Edmontosaurus was most closely related to which of these three animals?

What allows you to make that connection?

Now enter the Cenozoic Hall, or the hall of mammals. At the east end of the hall is a large display showing the horse fossils from different aged deposits with the Cenozoic Era. Describe the evolutionary changes in horses recorded by these fossils in the spaces below:

Size:

Teeth:

Toes:

Look carefully at the examples of camels and rhinos. Look at their feet. What characteristic can be used, based on feet alone, to tell these two groups of mammals apart?

Along the south wall are display cases with various parts of mammals in them. Find the display case that has the teeth of the mastodon and the mammoth. What are the differences in these teeth?

How does that give some indication of their feeding habit?