Investigating Evolution at Cincinnati Zoo and Botanical Garden




A fieldtrip for teachers at Centerville City Schools

August 14th, 2002








Michael Sandy,

Department of Geology,

University of Dayton





Michael Sandy, Department of Geology, University of Dayton


The aim of this fieldtrip is to investigate the biological development of life using examples from the Cincinnati Zoo and Botanical Gardens, and supplement these living examples with geological information on the occurrence of related forms in the fossil record. Therefore I hope the trip, which should be fun, will give you have an appreciation for past, present, and future life on Earth.

I realize that some of you may well be teachers of biology and may teach some of what we are doing today much more frequently than myself. Please do feel free to share your insights and experience with us. The main thing is that I hope we will all have an enjoyable time at the zoo!!

Acknowledgements: I have liberally copied images and text from the Tree of Life web site and the University of California, Museum of Paleontology, Berkeley web site in compiling this guidebook. The addresses can be found at the end of this guide.

Thanks to Cincinnati Zoo and Botanical Gardens for letting us explore their animals and plants, and Jillian Sandy for help with a logistical trip. Some of the equipment that helped in producing this guidebook was obtained through a project SUSTAIN grant.


There are some major topics that need some brief introduction:

Evolution -

While you are looking at the plants and animals at the zoo consider their adaptations. Certain animals (and plants) show obvious adaptations to various lifestyles - the sharp pointed teeth of the crocodile and dolphin are excellent ways to infer a carnivorous lifestyle just as the large grinding molar teeth of horses, cattle, and elephants indicate a herbivorous diet.

Look for adaptations to particular lifestyles as you look at the animals in the zoo today ….

Figure 1. Some examples of adaptation to different lifestyles from marine fish.

From Aquatic Life in the John G. Shedd Aquarium.

Much of our investigation of evolution today at the zoo will be based on observing adaptations to particular lifestyles or habitats.

In describing plants and animals around us biologists have observed a hierarchy of increasing complexity. Through geologic time the organization of life has become more complex, although it’s a pretty complex thing even when it’s simple! The fossil record shows that snails evolved after bacteria, lizards developed after fish, and mammals evolved after reptiles; the fossil record records the same story of increasing complexity, with time. With time organisms have evolved and developed new reproductive strategies.

The Geological Timescale -

Geologists divide time into divisions much as we do into days, months, and years in our day-to-day lives. An understanding of the geological timescale is important because different groups of animals originated at different times during the geologic past.

Figure 2. The Geological Timescale.

A much more detailed version is on the inside back cover of this guidebook.


The Paleozoic (Eon) is the time of “evident life” - shelly fossils became abundant.

Cenozoic (Era) present day to 65 million years ago = “Age of Mammals”.

Mesozoic (Era) 65-240 million years ago = “Age of Reptiles/Dinosaurs”.

Paleozoic (Era) 240-543 million years ago = “Age of Invertebrates”.

The Precambrian ranges from 4.6-0.54 billion years ago.

Figure 3. First appearances of the major vertebrate animal groups in the fossil record.

All of these are occurrences are during the last half-billion years of earth history. The timescale ranges from the Cambrian to the end of the Cretaceous, 65 million years ago. Detail from a poster in the “Frogs” exhibit, Cincinnati Zoo.

Cambrian - First abundant shelly fossils

First Fish - Ordovician (the Devonian is known as “The Age of Fish”)

First major coral reef developments - Silurian

First insects; first amphibians - Devonian

First reptiles; first mammal-like reptiles - Carboniferous

End of the Permian (is also the end of the Paleozoic), the Permo-Triassic extinction - largest extinction of life in the history of the earth

First dinosaurs; first mammals - Triassic

First birds - Jurassic

First primates approximately 8 million years ago

First Homo sapiens approximately 250,000 years ago.

Biodiversity -

Typically this is used to refer to the total number of species in an environment (lake, prairie) or the total number of living species (global biodiversity). It is usually a measure of number of species. Biomass is the weight of living matter and can be measured for an organism, the members of a species, or a group of animals.

Animal and plant classification -

The modern system of classifying all living plants and animals, and fossils, is called the binomial system, and was founded by Carl Linneaus. A genus and species is identified for each organism, Homo sapiens being one such example. Similar species may be grouped in a single genus (pl. genera); similar genera in families; families in orders; orders in classes; classes in a phylum (pl. phyla); on up to kingdom.

Carl Linnaeus, also known as Carl von Linné or Carolus Linnaeus, is often called the Father of Taxonomy. His system for naming, ranking, and classifying organisms is still in wide use today (with many changes). His ideas on classification have influenced generations of biologists during and after his own lifetime, even those opposed to the philosophical and theological roots of his work. (Second paragraph from



Dividing animals into invertebrates and vertebrates is a convenient classification.


Figure 4. Diversity among invertebrates.

From Aquatic Life in the John G. Shedd Aquarium.




Where did the first vertebrates come from .. what did they look like? The Urochordata ..

“sea squirts” of today, resemble what the first vertebrates may have looked like:

 Figure 5. A group of living sea squirts, probably about 2-3 cm in length. Source



Invertebrates and Vertebrates are all Eukaryotes

The Eukaryota include the organisms that most people are most familiar with - all animals, plants, fungi, and protists. They also include the vast majority of the organisms that paleontologists work with. Although they show unbelievable diversity in form, they share fundamental characteristics of cellular organization, biochemistry, and molecular biology. Shown here, clockwise from upper left: a dinoflagellate, a single-celled photosynthetic protist; a palm tree representing the plants; a spider, one of the animals; and a cluster of mushrooms representing the fungi.

Today we will be focusing on the animals!

Figure 6. The Eukaryotes



Acanthostega from the Upper Devonian

Ichthyostega from the Upper Devonian

First “four legged fish”


Major Exhibits at Cincinnati Zoo and Botanical Garden


The Cincinnati Zoo and Botanical Garden is located at the geographic center of the city. It has both outdoor and indoor exhibits on its 70 acres of grounds.

Landscape and Gardens
Officially renamed the Cincinnati Zoo and Botanical Garden in 1987, the award-winning landscape includes over 2,800 varieties of trees, shrubs, tropical plants, bulbs, perennials and annuals. Many plantings are designed to represent the natural habitats of animals on exhibit. Some of the most attractive plantings are found at the Children's Zoo, Monkey Island, Red Panda Exhibit, Gorilla World and the Central Lawn. Special gardens include the Dinosaur Garden, Butterfly Garden and Bird Garden. Many plants are labeled.

Botanical Center and Oriental Garden
This facility features an open garden pavilion where Zoo visitors can learn how plants and animals depend upon each other. The Japanese art of bonsai is featured in a special display area of the Botanical Center. The Oriental Garden is a representation of natural places and plant communities in a Japanese garden style setting which includes a pond filled with golden koi (Oriental goldfish).

Jungle Trails
Jungle Trails is a naturalized rain forest habitat, teeming with rare and exotic wildlife and hundreds of plant species from Asia and Africa. The exhibit, with both indoor and outdoor viewing areas, has become the home for the Zoo's collection of rare primates, including endangered bonobo chimpanzees, orangutans and lemurs. In addition, Jungle Trails houses birds and reptiles from Asian and African rain forest regions. Jungle Trails received the American Zoo and Aquarium Association's prestigious exhibit award in 1994.

Eagle Eyrie
Features American bald eagles, symbol of the United States, and Stellar's Sea Eagles. These birds are part of a major cooperative conservation effort; the Cincinnati Zoo has hatched and released many bald eagles into the wild since 1982. The exhibit features an observation deck that is actually inside the flight cage, so nothing can come between the visitor and the eagles.

Wildlife Canyon
Rare hoofed mammal species are displayed here. A male and female Sumatran rhino, Mhorr's gazelles, zebra duiker, takin, red river hogs and Bactrian camels can all be found in this area.

Monkey Island
Built in 1930 and renovated in 1985. This manmade rock island is surrounded by a moat and exotic landscaping and provides a home for Japanese macaques and blue sheep.

Red Panda Exhibit
Naturalistic woodland landscape includes many unusual Chinese plant species to simulate the natural forest habitat of the red panda. One pair of pandas is a gift to the Cincinnati Zoo from the Beijing Zoo, China.

Gorilla World
Opened in 1978 as a naturalistic, rain forest habitat for the Cincinnati Zoo's popular lowland gorillas. Other animals housed here are crowned guenons and colobus monkeys. Because of the success of our gorilla breeding program, Newsweek called the Cincinnati Zoo the "sexiest zoo in the country."

White Lions
Opened in 1975. This spacious exhibit shows off the Cincinnati Zoo's white lions. Walk over the Canyon bridge to view the lions unobstructed in a natural setting.

Gibbon Islands
Completed in 1972, Gibbon Islands occupies the former location of the old Opera Pavilion. (From 1920-1971, the Cincinnati Zoo was home to the Cincinnati Opera Summer Festival.) These two islands are surrounded by water that flows from Swan Lake. Bamboo exercise bars are the stage for white-cheeked gibbons and siamangs who entertain visitors with their acrobatic antics and loud whooping calls.

African Veldt
Built in 1935 and home to large hoofed mammals of the African veldt. Damara's zebra,Giant eland, bongo, and yellow-backed duiker, and African Flamingos all reside here.

Rhino Reserve
In 1997, this display opened, displaying the Zoo's Indian rhinoceroses in a large area, complete with fallen trees and a large pool.

Bear Line
Built in 1937, this area is home to American black bears, spectacled bears, and polar bears.

Lords of the Arctic
This spectacular new exhibit, which opened July 2000, features a naturalistic environment for our polar bears. Explore the coasts of the arctic and learn about this unusual habitat.

Cat Grottos
Built in 1934. White tigers, Indo-Chinese tigers and African wild dogs are displayed here.

Joseph H. Spaulding Children's Zoo
Renovated in 1984-1985. 55,000 square feet of exhibits that feature rare cousins of common barnyard animals (pygmy goat, pot-bellied pigs, zebu cattle), animals of the eastern U.S. woodlands, and animals of the southwestern U.S. desert. The Cincinnati Zoo nursery is also located here. Other Children's Zoo buildings include a Zoolab, Children's Forest and the Kahn's Children's Theatre. Participation is the key to Children's Zoo exhibits. The statue of Joseph H. Spaulding Jr. at the entrance is by Lazlo Ispansky. In 1997, "Blakely's Barn" addition opened, featuring rare, historic breeds of domestic livestock. "Otter Creek" features frolicking river otters in a naturalistic setting.

Frisch's Discovery Center
Renovated in 1989. This outdoor classroom, located near the Education Center, has seating for the public near animal holding areas. Live animal demonstrations for school groups and Zoo visitors are presented regularly during the summer.

Cat House
Opened in 1952 and renovated 1985. The Cincinnati Zoo has bred more species of rare cats than any other zoo in the world. The Cat House features hand-painted murals and artificial rockwork that depicts the natural habitat of 16 different cat species.

Award winning!
Insect World

Opened in 1978, this is the largest building in North America devoted to the display of live insects. The Cincinnati Zoo has been given four awards by the American Zoo and Aquarium Association for successful propagation of insects: the Hercules beetle, the Royal Goliath beetle, the Giant Southeast Asian Walking Stick and the Harlequin beetle. A display of naked mole rats, unusual for their termite-like social structures, is located here. Insect World received the prized American Zoo and Aquarium Association exhibit award in 1979.

Nocturnal House
Opened in 1964. Day and night light cycles are reversed to display the activities of many nocturnal mammal species, including aardvark, fennec fox, barn owls and many types of bats, such as vampire bats.

Manatee Springs
This exhibit interprets swamp and river habitats of Florida and the species that inhabit these areas. Close-up viewing on both dry land, as well as dramatic underwater viewing of magnificent animals, including charismatic manatees, provide an exciting experience for every Zoo visitor.

Wings of the World: "A Celebration of Flight"
Originally opened in 1936 and completely renovated in 1996. Wings of the World was first designed as a reptile building and is now a state of the art exhibit dedicated to birds. Elaborate artwork and hand-painted murals give life to this exhibit which houses a wide variety of birds, including puffins and auklets, as well as king penguins. Lavishly planted aviaries and displays provide habitats as natural as the outdoors. Birds from around the world are housed here.

Star Bank, Hillshire Farms and Kahn's Komodo Dragon Exhibit
Our male dragon is a gift from the President of Indonesia to former President George Bush, with the specification that the animal reside in the Cincinnati Zoo. The Komodo dragon, the world's largest lizard and one of the most dangerous reptiles, can grow to be 10 feet long and weigh over 300 pounds.


Vanishing Giants
Designed by Cincinnati-based Elzner and Anderson Architects and built in 1906. This is an early example of pour-in-place reinforced concrete. The building is a blend of Islamic design influences, giving a Taj Mahal-like appearance. The Elephant House was renovated in 1982, and 2000.

Reptile House
Built in 1875. One of the Zoo's original buildings, it first housed monkeys, but is now home to the Zoo's reptiles. The Reptile House is the oldest designed zoo building in America.

Passenger Pigeon Memorial
Built in 1875 as bird aviaries. The building was moved to its current location and renovated into this memorial in the mid 1970s. The Passenger Pigeon Memorial pays tribute to Martha, the passenger pigeon who was the last representative of her species. Martha hatched at the Cincinnati Zoo in 1888 and died here in 1914. This exhibit reinforces the strong conservation message that the Cincinnati Zoo hopes to convey in all its work. The last captive Carolina parakeet, Incas, died in 1918 and is also commemorated here.



Please note that in the indoor exhibits there is no smoking, food, drinks, or gum permitted.


Headings below in bold are what you can expect to see in INSECT WORLD

Insects and their relatives

What is an insect

Evolution - flying insects probably in the Devonian but in the Carboniferous Period dragon flies had wingspans of 18 inches (45 cm)

Most animals are insects > ¾ of 1,150,000 species known are insects. Beetles comprise >30% of all animal species

What is your weight in insects? _____________

Success of the Insect

Insects can fly

Some insects pollinate plants

Figure 7. Adaptations to different feeding styles among the insects in INSECT WORLD



Name the different feeding styles and name a representative insect from the INSECT WORLD models shown in Figure 7

_____________ ______________ ____________ ____________

_____________ ______________ ____________ ____________

What eats insects

Camouflage and Mimicry - what are the advantages of these?





There is a display of Naked Mole Rats - A Termite-like Mammal - blind burrowing rodents.

Metamorphosis - insects undergo major transformations in their life cycles

There are two major ways this can occur:

Complete metamorphosis

Gradual metamorphosis

What are the differences between these two types of metamorphosis and name some insects that belong to each type.




Which insect has a 17-year gradual metamorphism? ____________________

Solitary insects

Gregarious insects - social insects

There are live exhibits of social insects. Name some examples and what type of structures do they construct?





Butterfly walk - provides a glimpse of some of the interactions between insects and plants

Insect art/insect food

Evolution of the hive (beekeeping)



Assemble just outside the exhibit exit

Turn the page and confirm the biological affinities of the main residents of INSECT WORLD.

Did you only see invertebrates in INSECT WORLD?






Insects belong to the Phylum Arthropoda

Figure 8. Some representative arthropods

A classification of the Arthropods

Source Tree of Life web site




The focus here is on the ecosystems of Florida.

Check off the different types of vertebrate animals in the exhibit building from entrance to exit:

Live exhibit Static exhibit

Frog _______ _______

Toad _______ _______

Newt _______ _______

Salamander _______ _______

Fish _______ _______

Alligator _______ _______

Crocodile _______ _______

Bird _______ _______

Manatee _______ _______

other mammals?

_______ _______

_______ _______

other vertebrate groups?

_______ _______

_______ _______


What invertebrates did you notice in MANATEE SPRINGS?



Manatee aquarium - how many different types of vertebrates are in the tank?

Infamous Alien Invaders

Dater Discovery Center

Investigate the crocodile and alligator skulls - how do they differ?


How do the teeth of the Manatee differ?

Florida Biodiversity

The first 3 tanks that you come to … one tank has invertebrates - what are they?

MANATEE SPRINGS attempts to give an overview of Florida.

Population growth in Florida puts pressure on natural environments - Population of Florida in 1900 was < 1 million, in 2000 > 14 million



This is a traveling exhibit currently at the Cincinnati Zoo.

Frogs are amphibians. Amphibians are first known in the Carboniferous.

From the evolutionary point of view they are further developed from fish - we saw some in MANATEE SPRINGS. How do fish and amphibians differ?

There is a “living fossil” found today that has lobe-fins - it is thought to resemble closely an intermediate stage in the evolution of “fish fins” to “tetrapod limbs” (i.e., legs for walking)

Presumably this transition must have happened by the Carboniferous.

Do you know what this “living fossil” is called?

As you enter the exhibit you will see a monitor that shows that frogs metamorphose too … what stages do they pass through?

Largest frog is the Goliath Frog, nearly 1 foot (30 cm) long.

The Carboniferous was the “Age of Amphibians” as great coal swamps formed on river deltas draining the uplifting Appalachian Mountains and newly formed mountains in Europe.

In addition, these swamps were dominated by trees that were replaced later in geologic time by the conifers and deciduous trees that we know so well today.


26 salamander species

15 frog species

what other kinds of amphibians too?

Near the exit note the GIANT SALAMANDER

How long does the Japanese Salamander grow?


You may have to fight your way through the store …




We have seen many amphibians …

What changes are needed to evolve from a fish to an amphibian?



Similarly, what changes are needed to end up with a reptile from an amphibian?

Figure 9. Watch out for the ring-tailed lemurs!



Figure 10. The Komodo Dragon

This is a carnivorous reptile that can grow up to 10 feet (3 meters) in length.

What typically reptilian features does the Komodo Dragon exhibit?

Do you know how a modern reptiles differ from dinosaurs?


Here we will see adaptations to night life (this does not include gold medallions and neon license plate holders in this instance).

What adaptations to night life do you see?

What animal group do the following belong to (i.e., reptile, mammal, etc.)?




BINTURONG - only old world mammal with a prehensile tail (what is a prehensile tail?)

STRIPPED POSSUM - New Guinea, and Queensland, Australia





FEATHERTAIL GLIDER - forests and woodland of Eastern Australia - marsupial. The first mammals in the Triassic were very small, probably similar in size to these small mammals.



COQUEREL’S MOUSE LEMUR - lemurs are only known on the island of Madagascar off the East African coast

FAT-TAILED DWARF LEMUR - lemurs are early representatives of the primates, which includes hominids (humans)

more GIANT FRUIT BATS - watch out for your bananas!

AARDVARK - what do I eat? How do you know?


SLENDER BORIS - are you still awake?



How many different groups of flying animals did we see today? How many were vertebrates?

Do you think that the extinct flying reptiles of the Mesozoic (Pterosaurs such as Pterodactyl) gave rise to birds and/or bats? What evidence can you cite for your conclusions?

Figure 11. Everyone’s favorite … “How could you come and not visssit me?”


BIRDS OF THE WORLD - a great diversity of bird shapes and beaks related to lifestyles and diet.

JUNGLE TRAILS - a variety of primates and other mammals.

GORILLA WORLD - it is often thought that we are descended from modern apes. We share a common ancestry, but are not derived from apes.


Clearly there is something to observe and learn about evolution from any and all of the exhibits at the zoo - how about your cat or dog at home (if you have one), or your favorite resident sparrows, cardinals, and cockroaches?

Remember today’s rallying cry … “adaptation, adaptation, adaptation!!

- - - - - - - - - - - - -


The National Science Education Standards envision change throughout the system.

The teaching standards encompass the following changes in emphases:


Treating all students alike and Understanding and responding to

responding to the group as a whole individual student's interests, strengths,

experiences, and needs

Rigidly following curriculum Selecting and adapting curriculum

Focusing on student acquisition Focusing on student understanding

of information and use of scientific knowledge, ideas,

and inquiry processes

Presenting scientific knowledge Guiding students in active and

through lecture, text, and extended scientific inquiry


Asking for recitation of Providing opportunities for scientific

acquired knowledge discussion and debate among students

Testing students for factual Continuously assessing

information at the end of the student understanding

unit or chapter

Maintaining responsibility and Sharing responsibility for

authority learning with students

Supporting competition Supporting a classroom community

with cooperation, shared responsibility,

and respect

Working alone Working with other teachers to

enhance the science program

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The Tree of Life Web Project

Museum of Paleontology, University of California, Berkeley

Cincinnati Zoo and Botanical Garden