For Members of Lincoln Park Zoo 路 A Magazine of Conservation and Education 路 Winter 2014
Animal Anatomy
Exploring Differences from Tooth to Tail
IN THIS ISSUE Volume 13 Number 3 · For Members of Lincoln Park Zoo
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FEATURES The Whole Tooth
Impressive incisors, millstone molars—what an animal eats is often dependent on its teeth.
All Eyes…and Ears
From looking for prey to listening for a mate, animals depend on sight and sound to survive.
Wings, Paws and Claws
A tiger’s paw, a bat’s wing and a monkey’s nimble fingers are all adapted from the same basic building blocks.
The Right Tail for the Task
Whether you’re looking to spring, swim or steer, the right tail can go a long way toward pointing you in the right direction.
Mind Games
Applied brainpower was once believed to be a uniquely human adaptation, but zoo scientists are finding new ways to explore how animals think.
DEPARTMENTS Perspective
Adaptations are what make every animal unique— and every visit to the zoo so compelling, President and CEO Kevin Bell says.
The Secret Life of Trees
Winter awaits every tree, but coniferous and deciduous varieties have distinctive ways of coping with the cold.
News of the Zoo
Lionel Train Adventure opens its gates, the zoo celebrates “Monkey Business” and Chicago Wildlife Watch looks for your help IDing 1 million photos of local species.
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Wild File
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Calendar
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A big birthday for baby King, a Polar Bear Farewell Party and new faces throughout the zoo. What do you do at the zoo in winter? Strap on ice skates and get ready for the glow of ZooLights Presented by ComEd and PNC Bank!
Membership Matters
Member fun includes an exclusive Members-Only Night at ZooLights—and special chats for our most loyal supporters.
Continue Your Visit Online Visit www.lpzoo.org for Lincoln Park Zoo photos, videos and up-to-date info on events and animals. You can also find us on Facebook and Twitter! We'd Like to Hear from You! Send your feedback on this issue of Lincoln Park Zoo magazine to magazine@lpzoo.org. Cover: A jambu fruit dove uses grasping claws to perch at the McCormick Bird House. LINCOLN PARK ZOO MAGAZINE
QUESTIONS? Contact the Membership Department. Staff are on hand during normal business hours— phone 312-742-2322 or visit us online at www.lpzoo.org.
President and CEO Kevin J. Bell
Editor James Seidler
Art Director Peggy Martin
Communications Specialist Craig Keller
Designer Joann Dzon Lincoln Park Zoo, 2001 North Clark Street, Chicago, IL 60614, 312-742-2000, www.lpzoo.org. Lincoln Park Zoo is supported through a public/private partnership between the Chicago Park District and The Lincoln Park Zoological Society. The only privately managed free zoo in the country, Lincoln Park Zoo relies on membership, individual, foundation and corporate support as well as earned revenue.
perspective A Letter From President and CEO Kevin J. Bell
Adapted for Anything Each animal is adapted for its own world. That’s a big part of what makes a day at the zoo so fascinating. You can imagine along as harbor seals glide beneath the water, white-cheeked gibbons swing through the treetops and sunbitterns stretch their wings at the McCormick Bird House. The characteristics that make these species unique have each been shaped by the long tests of evolution. The bat’s wing, tiger’s paw and gorilla’s hand all come from the same ancestral building blocks. The same is true for the eagle’s eye, which can pinpoint prey from miles overhead, and the zebra’s elongated pupil, which nervously scans the horizon for predators. As you know, I started my career at Lincoln Park Zoo as the curator of birds, and I’ve always been fascinated by the adaptations that define this branch of the animal kingdom. All birds share certain features: wings, feathers, beaks. But it’s the differences in how these features have been shaped by time that makes
each animal what it is. In one niche you end up with the pincer-like talons of a snowy owl while in another you get the paddle-like “oars” of a trumpeter swan. Red knots use tiny wings to migrate more than 9,000 miles from the Arctic to the southern tip of South America every year. And groundbound ostriches wield relatively massive wings only for displays and regulating body temperature. People are animals too, and we have our own set of adaptations, notably the big brains and opposable thumbs that have transformed the world we all share. But as zoo scientists could tell you, the list of animals that “think” and use tools is growing ever larger. For 10 years now, researchers at the zoo’s Lester E. Fisher Center for the Study and Conservation of Apes have studied the cognitive abilities of chimpanzees and gorillas at Regenstein Center for African Apes. By studying our closest cousins, we can better understand how humans came to be human. At the same time, Fisher Center findings highlight new ways to better care for these impressive animals. Improving animal care—that’s an adaptation we’re always happy to encourage.
Kevin J. Bell President and CEO
Every animal at the zoo displays unique adaptations, from the sharp talons of a snowy owl to the nimble fingers of a gorilla or spear-like beak of a sunbittern.
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The Whole Tooth BY JAMES SEIDLER
As the zookeepers could tell you, nearly every animal at the zoo has a bite worth watching out for. But it’s understandable if certain chompers prompt extra caution from caregivers. It’s wise to keep your digits away from a dwarf mongoose (they are Africa’s smallest carnivore, after all). Similarly, a Moholi bushbaby may munch insects in the wild, but that doesn’t mean you want them mistaking your thumb a meal. Still, the top dogs in the tooth world are, unsurprisingly, canine. Those are the long, sharp fangs you see poking out of the corners of a prototypical predator’s mouth. Together with sharp incisors in front, they play a big role in gripping—and killing—prey.
Impressive canines help African lions grab prey while chimpanzees’ smaller versions are better suited for dominance displays. Cows have tiny teeth up front, but massive molars help them grind grass.
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Calling All Canines
Lions, tigers, jaguars, pumas, Pallas’ cats, red wolfs and African wild dogs are among the species with this distinctive “tooth-kit.” After they’ve made the kill, these predators shred protein from bone with scissor-like carnassials in back. Harbor seals and river otters also rely on a sharp set up front to snatch prey out of the water. Species that prey on insects and small mammals—meerkats, for instance—have largely the same framework, albeit reduced. “Meerkats actually have some pretty good teeth in there for being so small,” says Curator of Mammals Mark Kamhout. “It helps them be good hunters.” Aardvarks and armadillos take a different approach to dentition, however. These insect eaters lack canines and incisors entirely. Instead, they use a series of stubby “cheek teeth” to chew up insects. These small, enamel-less columns continually grow, and are worn down, over their lifetimes.
Another Sharp Set
The zoo’s reptiles also have sharp teeth for gripping and dispatching prey, but their dentition is relatively undifferentiated. Whether you’re looking at the biting end of a black tree monitor or dwarf crocodile, the teeth come from the same generic “pointy” playbook. One exception for the scaled set, though, is venomous snakes. These predators, including eastern massasauga rattlesnakes, have evolved formidable fangs to deliver venom. How does it work? Typically a duct connects a hollow fang to a venom-producing gland, enabling the snake to pump in poison at a bite…almost like a hypodermic needle.
adaptable for everything from chewing vegetation to gnawing meat to piercing the skins of fruits. Several non-human primates, including De Brazza’s monkeys and male gorillas, retain large canines for defense and display. “Our two male De Brazza’s have really long canines, and they display a lot,” says Curator of Primates Maureen Leahy. Even multipurpose primates have some special adaptations, though. Take the zoo’s crowned lemurs, who, like all lemurs, have a dental “comb” formed by the lower six incisors and canine teeth, which assists grooming for this social species.
Multi-Purpose Mouths
While carnivorous teeth are selected for their cutting edge, herbivores’ masticators focus more on endurance. (There’s a reason guests can feed the cows but not the big cats.) Because of this emphasis the herbivore’s dental makeup is mostly molar. Thick, grinding plates help committed plant eaters process and gain sustenance from nutrient-light foods such as leaves and grasses. Some species, such as Grevy’s zebras, have incisors in front to clip away grasses and shrubs for chewing. But many others, including giraffes, waterbucks, Grant’s gazelles, Sichuan takins and eastern black rhinos, lack the front teeth on top or in their entirety! Instead, prehensile lips (rhinos), long tongues (giraffes) or fleshy “dental pads” (cows and goats) help these specialists grip their leafy meals.
Omnivores at the zoo have mouths that do a little bit of everything: miniature incisors and canines to grip and mid-sized molars to grind. For instance, black bears’ impressive canines show off the species’ predatory roots, but in the wild they’re just as likely to use these teeth to rip open a log for grubs as to grab prey. Similarly, primates, including people, have all-purpose teeth,
Mill-Like Molars
Chewing on Cue
As you’ve seen, an animal’s teeth tell us a lot about its lifestyle. This is especially true for mammals, whose dental differentiation plays a big part in defining species and their niches. Just think of the difference between a beaver’s tree-felling incisors and our own relatively puny ones. Each highlights what the species does best…and gives it a signature look to boot.
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All Eyes… And Ears BY CRAIG KELLER
Whether they’re spotting prey or seeking a mate, animals depend on these senses to interpret the world around them. We take a peek—and listen in—on some standout features.
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Nightlife in the Treetops
By day, Moholi bushbabies seek safety in tree hollows. After dark, however, these tiny African primates (also known as galagos) reveal their true, nocturnal super powers. Their eyes—colorblind, equipped with special reflective layers behind the retinas and so big they can’t move in their sockets—provide superb night vision. Bushbabies compensate for immobile eyes with the ability to turn their heads 180 degrees. That helps these powerful leapers spot prey and predator. So do their huge, oval ears—proportionately the largest of any primate species. Complex ear folds enhance hearing so acute that bushbabies can pinpoint moths and other insects by sound in the dark. Zoo visitors can witness a similar behavior in the dimly lit bushbaby exhibit at Regenstein Small Mammal-Reptile House. “Keepers will scatter crickets, and you can see the galagos watching and listening before they pounce and grab the insects,” says Curator Diane Mulkerin.
Eagle Eye Exam
Eagles in flight can spot small prey far below and adjust the curvature of their eye lenses to maintain focus and depth perception throughout their approach and attack. The large eyes have limited muscle movement, but eagles compensate by being able to turn their heads 270 degrees. Each eye also has two fovea (humans have just one), a part of the
retina responsible for perceiving detail and color. One set of fovea provides binocular vision to the front while the other set provides monocular vision to the sides—combining to produce a panoramic field of vision. “An eagle can detect a fish under the surface of the water from hundreds of feet in the air,” says Hope B. McCormick Curator of Birds Sunny Nelson. “Their eyesight is four to six times greater than ours. We notice that with Ethan, the zoo’s bald eagle, when he locks in on some small animal in a bush many feet away that we can’t see or hear at all.”
Keeping Pupils in Line
Round pupils are common across the animal kingdom. So are the vertical-slit pupils seen in many nocturnal cat and reptile species. Next time you visit the Farm-in-the-Zoo, though, look a cow, goat, pony or Jacob sheep in the eye and consider a third shape: horizontal. Many animals—including zebras, camels, hippos, mongooses and toads—have such pupils. The goat version is starkly rectangular against a light-colored iris. In prey species like cows and goats, eyes on opposite sides of the head provide nearly 360-degree peripheral vision—a handy tool for spotting predators. The oval-shaped field of view, which limits forward, linear vision, is why horses and cows can become alarmed when approached from the front. Generally, animals with horizontal pupils are more near-sighted at the lower portion of their visual spectrum and more far-sighted at the top. That’s good for seeing food upclose while staying alert for predators but not so great for depth perception. When a cow bobs its head up and down it’s often trying to focus on an object and determine its proximity.
Desert Ears
North Africa’s fennec fox may be the world’s smallest fox, but its ears refuse to play along. The diminutive Saharan Desert omnivore stands just 8 inches at the shoulder while its oversized, bat-like ears measure 6 inches. Those ears dissipate body heat to help keep these animals cool in their hot, dry A fennec fox’s impressive ears let it hear prey under the sand of its desert home. Bald eagles use sharp eyes to hunt from far overhead, while Moholi bushbabies’ big peepers help them pick up insects in low light. In contrast, goats’ horizontal pupils let them keep their grazing in focus—and an eye out for predators.
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habitat. They’re also highly sensitive to low-frequency sound waves, an adaptation enhanced by enlarged tympanic bullae— bulb-shaped bony structures housing the ear’s sensory receptors. These noctural predators can hear beetles walking across the sand and small rodents burrowing beneath it. Fennec foxes can also discern minute differences between whines and whimpers in the calls of other fennec foxes and bolt into their burrows if they hear a predatory eagle owl or caracal (desert lynx) approaching. Fortunately for Minnie, the female fennec fox at Regenstein Small Mammal-Reptile House, predators aren’t an issue, so she can contentedly nap during the day.
Amphibian Amplifiers
The dyeing poison arrow frogs and Solomon Island leaf frogs at Regenstein Small Mammal-Reptile House don’t have outer ears (pinnae) at all. But, like all frogs, they do have exposed eardrums (tympanic membranes) on the sides of their heads behind their eyes. Just as with human hearing, sound waves vibrate the eardrum and are transformed via sensory hair cells and nerve fibers into electrical pulses the brain interprets as sound. These particular amphibians, though, have specialized nerves that help them identify the frequency specific to their species’ calls. Incredibly, their lungs also help them listen. Frogs have an air link between their lungs and eardrums. When receiving mating calls from other frogs, the right and left lungs vibrate at varying rates before passing sound waves along to the inner ear. The minute differences in pressure help frogs locate the caller in a habitat teeming with frogs.
Stealth Insurance
When it comes to locating prey by sound, barn owls—occasionally on view during education programs at the Farm-in-theZoo—are world-class stealth hunters. These nocturnal birds of prey can precisely locate mice, voles and other small mammals in utter darkness, even beneath vegetation and snow. Barn owls can determine the position of prey along a horizontal line via the split-second delay between sound reaching the left and right ears. The ears, called apertures, are asymmet6 LINCOLN PARK ZOO
Dyeing poison arrow frogs use slight differences in air pressure to pinpoint the calls of potential mates while barn owls’ faces act like receivers to pick up the noises of small prey.
rically situated (the left is higher than the right), which helps the owl determine the prey’s vertical location as well. A barn owl’s face is even shaped like a radar dish to guide sounds into the ears. Barn owls use specialized facial muscles to adjust this “receiver” when tracking prey. Their downy feathers are virtually silent in flight, so prey don’t hear them coming until it’s too late. And when the hunt is over, barn owls can turn to feathered ear valves called opercula to dampen the noise. The snowy owls at Regenstein Birds of Prey Exhibit share similar ear anatomy. “They’re a diurnal species that hunts at all times,” says Nelson. “Last spring, despite being surrounded by their overgrown nest, our pair could still detect rabbits on the far side of the exhibit next to them. They also know when we’re coming—they start vocalizing to each other before they can see us.”
field note
Antlers and Horns BY MARK HOLLANDER
Sharp, spiraling points, blunt battering rams—the zoo’s hoofstock varies significantly in their headgear. Before we elaborate on individual features, though, let’s break down the difference between horns and antlers. Horns are two singular bones covered with keratin—the same material as our fingernails. Depending on the species, they can grow on males or both genders in a range of different shapes, sizes and colors. “The variation is just a matter of natural selection,” says Diane Mulkerin, curator of the Antelope & Zebra Area. Want to see the array of colors, shapes and sizes for yourself ? No problem. Sichuan takins, waterbucks (below) and Grant’s gazelles can all be seen at Lincoln Park Zoo. Sichuan takins are known for their short, curled horns while waterbucks and Grant’s gazelles’ are straighter and longer. Although horns almost always come in pairs, there is one outlier at the zoo, explains Curator of Mammals Mark Kamhout. “Our male Grant’s gazelle only has one horn but still does just fine and interacts appropriately with the female,” says Kamhout. The gazelle’s other horn was lost in an old injury at a previous institution. So, how do antlers differ from horns? “Horns are permanent, bony structures covered in keratin,” Mulkerin explains. “Antlers grow seasonally and are usually much larger, branched and heavier than any horns. Usually only males grow antlers with the exception of caribou and reindeer.” The white-lipped deer at the zoo (top) is a great example of strong, beautiful antlers. “He typically drops his in spring and begins growing a new set immediately,” says Mulkerin. “While growing they are covered in velvet, which helps them to grow.” The antlers reach full size by late summer, at which point the velvet is shed, exposing just the bone. If you plan to visit the zoo in the months ahead, you can expect plenty of horned animals. For antlers, though, don’t delay too long…or you might find yourself waiting until summer.
ANTLERS
HORNS
Antlers are covered in velvet as they grow—and they later fall off every year. Horns are permanent, consisting of two bones covered in keratin.
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Wings, Paws and Claws BY JAMES SEIDLER
Human hands are pretty…handy. Nimble fingers and an opposable thumb open up a lot of possibilities. The human hand can handle everything from performing open-heart surgery to—for the less spectacular among us—scratching out a legible grocery list. But human hands have their shortcomings too. No matter how long you let your fingernails grow, you’re not going to compete with the clutching power of an Amur tiger. Nor will your hands enable you to take flight like a straw-colored fruit bat or trot over the plains like a Grevy’s zebra. Whether you’re looking at a chef’s callused palms or an eagle’s sharp talons, extremities offer a nice shorthand as to what each individual does best. Learn more with this overview. 8 LINCOLN PARK ZOO
STEPHEN BELCHER/MINDEN PICTURES
Amur tigers and dwarf crocodiles rely on strong claws to snag prey while bats take to the skies with modified hands making up wings.
Sharp Stuff
If your diet depends on catching prey, it helps to have some pointy projections to help you hold it. A number of zoo predators rely on claws and talons to get a grip on the animals they eat. As you’d imagine, the big cats at the Kovler Lion House have some sharp stuff at the ends of their paws. The Amur tigers, African lions, Eurasian lynx, jaguar, Pallas’ cats, pumas and servals all possess formidable claws for grasping prey. Big-cat claws are notable for having the ability to extend and contract on command. The common term, “retractable,” is actually a bit of a misnomer, as cats’ claws are relaxed by default and only appear when desired. This dual ability keeps claws sharp and also prevents their bearer from making noise—or getting snagged—when running or stalking prey. Birds of prey, by contrast, always have their talons ready. Bald eagles descend on fish with talons outstretched—three in front, one facing forward in the back—closing a vice-like grip to carry prey back to their aerie. Snowy owls, on the other hand, have their talons arranged in an “x” pattern—two in front, two
in back—giving small mammals little chance of escape. Dwarf crocodiles have claws in front to help grab prey in the water, with the back feet webbed for a stronger swimming stroke. And while aardvarks don’t snag prey with their paws, the species’ impressive nails act like a shovel to dig ants and termites out of their mounds. “They’re very imposing,” says Curator of Mammals Mark Kamhout.
Moving Around
Of course, handbones have more uses than just getting a grip. Species across the zoo use specially adapted digits to get around. Take the Egyptian fruit bats that make their homes at Regenstein Small Mammal–Reptile House—and fly in colonies across Africa and the Middle East. As seen in silhouette, their wings are basically composed of a modified hand, with fingers stretching from top to bottom to lend support and flaps of skin in between catching air to let the mammals take flight. Birds also have modified hands within their wings, although their flight anatomy is different from bats. More of the arm extends into their wings, with lightweight finger bones fused to-
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Chilean flamingos have arms adapted for flight while chimpanzees use nimble fingers to wield tools to “fish” for termites.
gether to provide flapping support. Thick feathers play a big role in flight, helping species from Chilean flamingos to bald eagles achieve thrust and lift. “Sometimes wing coloration lets you distinguish the flight and non-flight feathers,” says Hope B. McCormick Curator of Birds Sunny Nelson. “The black feathers on the edge of the flamingo wings are their primary feathers, for instance.” The zoo’s harbor seals also use adapted paws to help them swim through the water. “Elbows” and “ankles” are contained within their streamlined bodies, meaning just the forearms, hands and feet provide the foundation for their paddle-like flippers. Another “hand” structure adapted for locomotion are the hooves seen on grazing species throughout the zoo. Composed of kertain, hooves are basically modified nails. They act to lengthen the stride and reduce contact with the ground, boosting speed and endurance. Hoofed mammals (also known as ungulates) are commonly divided into two groups. The hooved odd-toed ungulates— horses and, at the zoo, Grevy’s zebras—run on what’s essentially their third toe, with the other toes having disappeared or fusing against this single digit. Even-toed ungulates—including Grant’s gazelles, Bactrian camels and white-lipped deer—typically run on two hooved toes, the third and fourth. The dual platform may enhance grip and maneuverability on uneven surfaces. 10 LINCOLN PARK ZOO
Master Manipulators
While hooves and flippers offer fine examples of locomotion, they don’t offer much in terms of flexibility. Primates, though, use long, dexterous fingers and opposable thumbs to accomplish a variety of tasks. Movement is one of them. Brachiating species, such as white-cheeked gibbons, have long fingers and a reduced thumb to enable their rapid, hand-over-hand swings through the treetops. Colobus monkeys also have a reduced thumb, likely so the digit doesn’t get in the way of landings as they take great leaps through the canopy. (Indeed, as Curator of Primates Maureen Leahy shares, the species’ name, colobus, is derived from the Greek word for “mutilated,” a reference to their thumbs.) But many primate species have well-developed thumbs that help them manipulate objects and gather food ranging from fruits to flowers. Humans aside, the chimpanzee use of modified leaves and stems to “termite fish” may represent the height of manipulation, although monkeys are no slouches in that department either. “Our male swamp monkey, Boko, can manage everything from unscrewing nuts and bolts to untying multiple layers of knots,” says Leahy. It may not be open-heart surgery, but you can see the parallels.
field note Insects
LEAFCUTTER ANT
WALKING STICK
When most of us think of “animals,” we typically picture a subset of animals: vertebrates, which encompass everything from fish to reptiles to birds to ourselves. But the full animal kingdom is much larger than that. Jellyfish, lobsters, leeches, oysters, insects—they’re all animals. Your typical “animal” animal has a pretty familiar framework: a head, a torso, four limbs. Maybe there’s a tail, maybe the limbs have evolved into wings or flippers or are absent entirely (what’s up, snakes)? But that’s basically it. Focusing on insects, though, you see right away they’re built from a different blueprint. They have three body segments: the head, thorax and abdomen. The head supports the mouthparts, antenna and compound eyes. The thorax anchors the legs and any wings. And the abdomen houses the digestive tract, reproductive organs and possibly a stinger (watch out!). The differences don’t end there. Insects have six limbs compared to our four. Their bodies are supported by an exterior exoskeleton as opposed to our interior, boney version. Bugs breathe through tiny holes in their abdomens (spiracles), which carry oxygen to the rest of the body through a series of tiny tubes. They also have an open circulatory system, meaning the insect equivalent of blood is carried to the brain and just sort of oozes back through the body. Lincoln Park Zoo only has three insect species on display: the leafcutter ant colony at Regenstein Small Mammal-Reptile House, the Madagascar hissing cockroaches at Regenstein African Journey and the walking sticks at the Pritzker Family Children’s Zoo. The ants use powerful mandibles to cut and carry leaves back to their fungal farms. The cockroaches actually make their signature “hissing” sound by forcing air through their spiracles. And the walking stick blends into its native branches with a modified body and legs that look like, well, sticks. They may not be the “animals” we’re used to, but they’re fascinating in their own right. So next time you see an insect—at the zoo or in the great outdoors—why not lean in a little and try to appreciate what makes us different?
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Beaver tails handle everything from steering in the water to storing fat. Howler monkeys use prehensile tails to hang around, red kangaroos look to theirs for leaping power and Mexican lance-headed rattlesnakes shake theirs as a warning.
Multitasking Tail
DONALD M. JONES/MINDEN PICTURES
The Right Tail for the Task BY CRAIG KELLER
From a beaver’s bottom to a black howler monkey’s prehensile “fifth limb,” many animals rely on an extra appendage that humans lack. 12 LINCOLN PARK ZOO
Talk about an all-in-one tool. American beavers use their sturdy, paddle-shaped tails in several ways. Covered in leathery black scales, measuring up to 12 inches long and 5 inches wide and able to turn in four directions, it makes an efficient steering rudder for diving and swimming underwater. Beavers also use their tails to balance while gnawing through trees and when walking on hind legs while carrying mud and materials for building lodges and dams. The tail can also double in size from spring to fall with energy-storing fat reserves for winter. These nocturnal aquatic mammals even use their tails to communicate. Beavers slap it on the water’s surface to alert family members when predators approach. “Or, in general, when they’re startled,” says area Curator Diane Mulkerin. “When keepers bring the two female beavers a tree to snack on in their exhibit at the Pritzker Family Children’s Zoo, they’ll do the tail slap to signal each other.”
Fifth Limb
Black howler monkeys impress with their namesake long-distance howls and keen sense of smell, but their tails deserve a shout-out too. The large, treetop-dwelling primates use these strong, prehensile appendages like a fifth limb while feeding on leaves and fruits in their native Central and South American tropical forest homes. “They can locomote and support their entire body weight just by hanging from their tails,” says Curator of Primates Maureen Leahy. “The prehensile part wraps about one and a half times around a branch or vine for a tight grip.” The tail can measure 3 feet or longer and has a hairless underside with sensitive tactile pads. These help identify textures and objects and have unique prints just like finger tips. That’s a helpful adaptation for an animal that spends much of its time foraging in the forest canopy and rarely descends to the ground. Arrive at the Helen Brach Primate House when it opens at 10 a.m. and you may see zookeepers using a cable-and-pulley
system to raise a beehive-looking enrichment feeder high up in the black howler monkey exhibit—home to one male and two females. “We encourage arboreal foraging,” says Leahy. “They can’t stand on a branch below to reach it, so they have to hang from their tails instead.”
Down Under Adaptation
Powerful hind legs aren’t all that propel a red kangaroo forward. When the world’s largest marsupial hops about, its thick, strong tail provides balance between those massive hind legs, which can’t move independently. When a red kangaroo really gets motoring across its native Australian terrain the tail becomes part of a five-“legged” gait in which the smaller forelimbs and tail balance the animal as the hind legs move forward. It’s an effective method for mobility: red kangaroos can reach speeds exceeding 35 miles per hour and bound 25 feet in a single leap. During the day, when kangaroo mobs are mostly sedentary, the tail functions as part of a tripod with the hind legs for resting. Young males challenging each other for alpha-male breeding rights wield their tails in so-called “boxing matches” that mostly involve forelimb jabs and grappling. When fights become fierce males balance their bodies entirely on their tails, rear back and deliver powerful hind-leg kicks to their opponents.
OWEN NEWMAN/MINDEN PICTURES
Fanny Fan
Animal tails needn’t be athletic wonders to serve an important function. In the case of pygmy hippopotamuses—a reclusive semi-aquatic mammal native to West Africa—tails are all about waste disposal…and advertising. When pygmy hippos defecate in rivers or swamps they wag their tail to disperse feces. The zoo’s male and female pair do likewise in their pool at Regenstein African Journey. That tail, tipped with bristled hairs, performs the same ritual on land after dark when these solitary herbivores plow trails through dense forest to forage for plants and fruits. Vigorously fanning it to spread feces is an effective territory-marking method.
Rattle Royale
Next time you view the two male Mexican lance-headed rattlesnakes at the zoo’s Regenstein Small Mammal-Reptile House, consider that iconic rattle’s origin and development. Rattlesnakes are born with a single large, rounded scale on their tail tips. When the snake first sheds its skin that scale becomes a “button,” and the process is repeated every year as the snake sheds throughout its life. The resulting rattle—a series of these loosely attached, hard, hollow, interlocked segments— doesn’t grow to extraordinary lengths, though, due to daily wear-and-tear or narrow escapes from another predator. Rattlesnakes hold their rattles aloft to protect them as they travel. The built-in noisemaker sounds an alarm to predators or large animals that stray too close to these venomous reptiles. Specialized tail muscles can vibrate the rattle 50 times per second for up to three hours. Eastern massasauga rattlesnakes—which zoo researchers and caregivers study and raise for potential reintroduction in their native Midwestern range—are one exception to that general rule. “They’re a cryptic species whose line of defense is to remain hidden and quiet as long as possible,” says Mulkerin. “Some bigger species will start rattling when you’re 3 feet away from them.” For many species, it seems, if you’ve got a tail, you might as well use it.
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Mind Games
BY JAMES SEIDLER
As animals go, people have a few shortcomings. We don’t have claws or prehensile tails or tough, scaly hides. Seeing in the dark is a challenge, and our olfactory receptors can barely pick up cues from the next cubicle over (although sometimes that’s a blessing). But we do have some impressive brains. The evidence for that is indisputable, extending all the way from the satellites whirring overhead to the phones in our pockets. Art, language, science, machinery: they’re all byproducts of the human brain, representing a unique ecosystem—terra cerebrum—that was once thought to belong to us alone. But in recent decades scientists have realized that animals have colonized this landscape as well. Species including dolphins, chimpanzees, elephants, octopuses and even crows have displayed a range of self-awareness, tool use and problem-solving skills.
A Center for Cognition
Some of the earliest evidence for these “higher functions” in animals came from Jane Goodall’s groundbreaking work with chimpanzees at Tanzania’s Gombe National Park. There, the renowned scientist documented chimpanzee tool-use and culture, transforming our understanding of what animals are capable of. This revolutionary work was certainly on the minds of zoo scientists when the Lester E. Fisher Center for the Study and Conservation of Apes—and the groundbreaking Regenstein Center for African Apes—opened back in 2004. Indeed, the center’s initial director, Elizabeth Lonsdorf, Ph.D., did her graduate research at Gombe under the Jane Goodall Institute’s Center for Primate Studies. But the Fisher Center, launched with a grant from the Leo S. Guthman Fund, which has provided vital, continued support, found its projects soon moving in directions that weren’t possible in the wilderness of Africa. “One of our first projects was using a termite mound to see how naïve chimpanzees picked up a tool-use behavior that had been observed in Gombe,” says current Fisher Center Director Steve Ross, Ph.D. “But we quickly took advantage of the zoo 14 LINCOLN PARK ZOO
setting to do projects that wouldn’t be possible in the wild.” Try, for instance, to get Gombe’s wild chimpanzees to sequence symbols on a touch-screen computer. (Better yet, try afterward to submit a grant explaining why you need funding for another touch-screen computer.) But the zoo setting offered a perfect place to familiarize gorillas and chimpanzees with the new technology…and 10 years later, sequencing stars like western lowland gorilla Azizi have progressed to stringing together sequences from memory after only seeing the symbols for an instant.
Understanding Apes
Of course, Fisher Center scientists don’t only do sequencing studies because they’re cool. (And make no mistake, they are cool—you can see for yourself most afternoons at Regenstein Center for African Apes at 3:30 p.m.) The touch-screen studies, along with the full range of Fisher Center research, are motivated by a desire to better understand how these complex animals think. “We want to understand these animals so we can provide them the best possible care,” says Fisher Center Research Scientist Lydia Hopper, Ph.D. Luckily, the zoo’s scientists have a variety of tools to help them at the task. Handheld data recorders help interns catalogue everything from how chimpanzees and gorillas use their habitat to how they spend their days.
Scientists with the Lester E. Fisher Center for the Study and Conservation of Apes have spent 10 years studying chimpanzees and gorillas at Regenstein Center for African Apes.Tool use and touch-screen sequencing are among the amazing abilities on display.
A new project initiated by Hopper when she arrived in 2012 used little tokens to study how much chimpanzees were willing to “work” for variable rewards. By setting up an exchange system that delivered basic foods close by and preferred foods further away, Hopper, collaborator Kristin Bonnie, Ph.D., and Research Assistant Laura Kurtycz effectively debuted a nascent economy in Hank’s chimpanzee group at Regenstein Center for African Apes. As with any economy, there were winners and losers. The token system produced participants who played by the rules (Optimus) and others who took advantage of those playing by the rules (Kathy). It even spun off participants who learned to “pay off ” token grabbers to get their own treats (Chuckie) as well as an alpha male who largely opted out (Hank). “We’ve found through previous work that abilities are associated with the animals’ personalities,” says Hopper. “We’re always looking to design projects that are nuanced enough to show these individual abilities.”
Excitingly, this winter zoo researchers will also be adding a new species to the mix: Japanese macaques. Like Regenstein Center for African Apes before it, Regenstein Macaque Forest will have research integrated into the exhibit design, including observation windows, a “research cube” with touch-screens in booths and even a special tunnel offering ground-level observations of the exhibit. “It’s a new opportunity to build on the work we’ve done with Regenstein Center for African Apes,” says Ross. “We’re always looking for additional ways to build our knowledge—and improve animal care.”
Looking to the Future
The next 10 years for the Fisher Center are sure to hold new technologies, new projects and new partners. Zoo scientists will find additional ways to explore the minds of the chimpanzees and gorillas at Regenstein Center for African Apes. They’ll complement local studies with work a world away as Research Fellow Dave Morgan, Ph.D., continues to survey wild tool-use and culture in apes in the Republic of Congo’s Goualougo Triangle. (No word as to whether the Goualougo Triangle will be getting a touch-screen anytime soon.)
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The Secret Life of Trees
BY CRAIG KELLER
As fall gives way to winter, we take a closer look at how the zoo’s trees adapt to the change.
Seeds of Construction
Broad leaves that fall off in autumn versus needles that remain intact through winter may seem like the distinguishing factor between deciduous trees and conifers. Really, though, it comes down to sex. “Botanists will only make decisions off the sexual features of a tree,” says Director of Horticulture Brian Houck. “Leaves are not as important as how the seed and fruit are developed.” Conifers such as the zoo’s fir and spruce trees are gymnosperms, and broad-leafed flowering plants like maple and oak are angiosperms. The first term loosely translates as “naked seed” while the second means “vessel seed.” Conifers evolved first. Their seeds are exposed to the air, making them more susceptible to insects and disease. The fruits of angiosperms provide a more protective seed coat. “They’re a more recent evolutionary adaptation,” says Houck. Conifer cones are divided into female and male varieties. The former is easy to recognize—the familiar woody structure of a female pine cone, for example. The latter, not so much. “The male cone is more fleeting and generally smaller and skinnier,” says Houck. “It releases lots of pollen in the spring and then sort of falls off.” Pollination in conifers generally occurs through wind dispersal, although native coniferous forests also depend on occasional fires to regenerate. “Flames heat up the cone, which explodes and releases the seeds with a bang,” says Houck. “Obviously, we don’t do that here, but it’s been a big part of forestry management changes out west in the last century.” For deciduous trees and other
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angiosperms, wind, insects and birds all play roles in pollination. “The fruits attract animals, who pass it through their digestive systems and disperse the seed elsewhere,” says Houck. “It arrives with great compost and fertilizer to get it started.”
A Closer Look at Leaves
We tend to equate evergreens with winter, but needles and broad leaves represent two different ways of achieving the same goal: water and nutrient conservation. Needles, in fact, are leaves. They lose less water because they have less surface area and more succulent adaptations, such as a thicker, waxier outer skin called a cuticle. “Think of it like an orange rind,” says Houck. “It’s thick with some softer stuff in the middle.” Deciduous leaves have a similar anatomy but also more stomates—mouth-like pores that plants use to exchange carbon dioxide and oxygen with the atmosphere. A thin, spongy maple leaf dries out more quickly than a needle leaf largely because its stomates (more numerous on the leaf ’s underside) let water escape. “This is the reason we have fall color,” says Houck. “The tree pulls any mobile nutrient out of the leaf, stores it in the trunk and just gives up on the cheap material that can’t be reused. When a deciduous tree loses its leaves it’s protecting itself from drying out. It has adapted to make it through winter’s drought by changing its body.” From a plant’s perspective, the Chicago winter is a desert: no water unless snow melts on a warm day. Trees in colder climates undergo a “hardening” process as a defense against freezing during winter. Carbohydrates are transferred to the roots, sugars are stored in cells’ protoplasm and cell membranes become more permeable so water can seep into voids between cells, where it won’t cause irreparable damage when it freezes. Since they retain their leaves, conifers and other evergreens can actually grow a bit on sunny winter days through photosynthesis. Snow slides off their pyramidal shapes, which helps keep leaves moist and branches intact, but the zoo’s conifers get some extra help from zoo gardeners. “After a heavy snowfall we knock the snow off before branches break or the snow turns to ice,” says Houck. “So get a broom, go out and beat up your trees,” he adds with a wink.
Deciduous trees react to cooler temperatures by withdrawing nutrients from their leaves, producing the spectacular colors we associate with fall. Conifers, in contrast, maintain their color with small, waxy needles. (Gingkos, opposite, belong to the same biological group as conifers but shed their leaves in winter.)
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news of the zoo
The Urban Wildlife Institute recently launched www.chicagowildlifewatch.org, which is asking for your help to identify 1 million photos of local wildlife! Other zoo fun this summer included Adults Night Out and the impressive elegance of Zoo Ball, presented by Guggenheim Partners, LLC.
Lionel Train Adventure Roars to Life
Hobbyists have been stoked about Lionel Trains since 1900, the year the iconic model train manufacturer was founded. On Thursday, October 2, they had a bigger cause for celebration: the debut of Lionel Train Adventure at Lincoln Park Zoo. The exciting new attraction is located near the zoo’s West Gate and just south of Regenstein Macaque Forest. The trackless 28-passenger train crosses over a quaint country bridge and wends its way past forest and canyon scenery before returning to a red brick station. It features a coal car and a wheelchair-accessible caboose. On its opening weekend, the first 50 passengers per day received a free Lionel wooden train whistle and Lincoln Park Zoo members rode free. Tickets—priced at $3 per ride per passenger—are sold seasonally at the station.
Macaques on Track
Regenstein Macaque Forest is also on track to be fully completed by spring 2015. This spectacular home for Japanese snow monkeys will feature more than 10,000 square feet of outdoor exhibit and indoor animal-care space, with forested, rocky terrain, a hot spring and flowing streams evoking the primate species’ native habitat. Equipped with webcams, the exhibit will combine cutting-edge behavioral and cognitive research with educational learning programs.
Better than Counting Sheep
Citizen scientists, we need your help! Over the past few years, researchers at the zoo’s Urban Wildlife Institute have documented wildlife across the Chicago metro area with motion-triggered cameras placed at more than 100 sites. The results are staggering: more than 1 million photos of species from racoons to coyotes. And that’s where you come in: we need help tallying it all up. To accomplish this monumental task, the zoo has partnered with the Adler Planetarium, which has led several web-based citizen-science projects. Together we’ve created a new one, Chicago Wildlife Watch, at www.chicagowildlifewatch.org. 18 LINCOLN PARK ZOO
The process is simple. We'll show you one of the 1 million photos, and you’ll select the species, from a set of choices. If you get stumped on the animal ID, there are filters to help you narrow it down. Happy IDing! Your help contributes to our research into urban biodiversity, making the city a better home for both humans and animals.
Taking Learning Into the Community
Last year zoo educators helped implement a One Book One Community partnership with students reading “The One and Only Ivan” at five Wilmette primary schools. The months-long project included presentations at schools on zoo-led ape conservation and care, using the zoo’s Observe to Learn ethogram iPad app on field trips to Regenstein Center for African Apes, fundraising for gorilla care via the zoo’s ADOPT program and a public appearance and reading at the zoo by author Katherine Applegate.
Summer Nights to Savor
The past summer was filled with big events that entertained guests and supported Chicago’s free zoo. On July 11, the Women’s Board of Lincoln Park Zoo hosted the 37th annual Zoo Ball, presented by Guggenheim Partners, LLC. Themed “Monkey Business,” the gala benefit raised more than $1.2 million for zoo developments including the new Regenstein Macaque Forest exhibit. Locally Sourced at the Patio, sponsored by Lagunitas Brewing Company, brought fans of live acoustic music, DIY art, farm-fresh produce and craft ale to the Patio at Café Brauer on Wednesday evenings throughout the season. The after-hours fun continued with Zoovies. This free event, sponsored by Lagunitas, Aquafina and Naked Juice, attracted film lovers to monthly screenings on the South Lawn. Adults Night Out, a new offering held June 6 and August 8, treated grownups to bars and food stations throughout zoo grounds along with expert chats, special enrichment for the animals and free carousel rides.
wild file Big Birthdays and a Polar Party
If your ideal summer soiree includes cardboard cakes or raw herring hors d’oeurves (hey, we won’t judge), then Lincoln Park Zoo was your place this season! Animal care staff—and the animals themselves—enjoyed an impressive array of enrichment to mark some milestone birthdays…and one zoo farewell. White-cheeked gibbon Daxin kicked off the fun in celebrating his first birthday at the Helen Brach Primate House on August 16. A birthday banner, confetti and cardboard “cupcakes” containing fruits and nuts were among the treats crafted by the zoo’s Volunteer Enrichment Group. His fur now nearly allblack, Daxin clung close to mom Burma as they grazed their special goodies. The next animal event was more bittersweet as the zoo hosted a Polar Bear Farewell Party on August 23 to bid adieu to polar bear Anana. The powerful predator, who made her home at Polar Bear Plaza since 2001, was toasted with icy treats as guests signed farewell banners and watched her dive through her exhibit one last time. Anana traveled to North Carolina Zoo this fall as work began on the zoo’s new, state-of-the-art Polar Bear and Penguin Habitats. Finally, black rhino King turned 1 on August 26, with a cake sufficient to match his 1,000-pound stature! Composed of eight rhino-sized slices, with tasty browse and a faux candle topping them, the special enrichment offered a fun tribute to King and a species facing a conservation crisis in the wild. (Like most 1-year-olds, he was happy to hang back and let mom take the lead on the birthday fuss.)
Open the Hatches
The McCormick Bird House’s Free Flight Area welcomed a tiny Inca tern in July. This South American seabird is notable for the wavy mustache-like projections on each side of the beak. The “mustache” is a sign of maturity…although this tiny chick seemed to bear faint traces of the marking even before he fledged. The little birds weren’t the only ones breaking out of their shells. The zoo welcomed the hatches of nine smooth green snakes in July. The tiny insect eaters came to the zoo as eggs, part of a new local conservation partnership with the McHenry County Conservation District (the zoo has worked with the Lake County Forest Preserve District to restore the species since 2010). The small snakes will spend the winter getting a healthy head start at the zoo before a potential release in 2015. The same is true for the 11 ornate box turtle hatchlings that hatched behind the scenes in September. This native species, threatened in Illinois, will spend a year growing at the Kovler Lion House before returning to the wild.
New Zoo Species
Beyond the healthy hatches, Lincoln Park Zoo also welcomed two new species at the Antelope & Zebra Area. Three Chacoan peccaries are now living high on the hog in one of the area’s
White-cheeked gibbon Daxin celebrated his first birthday August 16 with special treats—and a snuggle from mom Burma. A Muscovy duck has joined the alpaca herd while Chacoan peccaries are having a “swine” time at the Antelope & Zebra Area.
northern exhibits. Native to Paraguay, Bolivia and Argentina, this social swine is adapted to the dry, hostile climate of South America’s Gran Chaco Region. Small herds spend much of their time using flexible snouts to dig for succulent plants. Specialized kidneys and two-chambered stomachs help the peccaries conserve water and break down cacti acid. Not too far away, a Muscovy duck is now sharing space with the zoo’s alpaca herd. Found from Mexico into South America, this waterfowl species is notable for the thick red markings on their faces. Males raise large crests on top of their heads to attract mates, and females build their nests in empty tree cavities. WINTER 2014 19
calendar
Good to Glow
ZooLights Presented by ComEd and PNC Bank has been a holiday highlight for nearly 20 years—not just at the zoo, but throughout the city as well. There’s no better place to experience a Chicago winter than with 2 million lights in gleaming displays at Lincoln Park Zoo. Beginning November 28, and extending select dates through January 4, visitors can get their annual dose of holiday crafts, sweet treats and Santa Claus...along with rides on the new Lionel Train Adventure! Another new addition to the schedule this year include BrewLights Presented by Louis Glunz Beer. On December 3, the Lincoln Park Zoo Auxiliary Board will host a special night of Louis Glunz Beer sampling from 5:30–9 p.m. Registration ($35) includes a hole-punch “ski ticket” good for 12 beer samples, many of which will be holiday themed, such as Delirium Noel and Anchor Steam Christmas Ale. The zoo is also excited to host its second annual Members-Only Night at ZooLights on Thursday, December 4. The special evening offers Lincoln Park Zoo members exclusive access to the lights and animals—but without the crowds. The winter fun also extends to Ice Skating at Lincoln Park Zoo, which is open daily from November 28 through March 1 (except December 24 and 25). A $5 entry fee, and $5 more to rent skates if you don’t have them, will let guests practice their spins, dips and turns under the shimmer of holiday lights at the Farm-in-the-Zoo. by Mark Hollander
Upcoming Events November 28–30; December 5–7, 12–23, 26–31; January 1–4 ZooLights Presented by ComEd and PNC Bank December 3 BrewLights Presented by Louis Glunz Beer December 4 Members–Only Night at ZooLights Holiday fun at the zoo includes cookies for kids, the brilliance of 2 million lights and rides on the new Lionel Train Adventure.
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November 28–30; December 1–23; December 26–March 1 Ice Skating Sundays, December 14, 21 or 28 Family Polar Parties December 29–31, January 2 Winter Break Camp
See the full calendar at www.lpzoo.org/calendar.
membership matters Members-Only Night at ZooLights
Last holiday season more than 2,000 zoo members and their guests had ZooLights all to themselves for one special night. The perk was so popular we’re offering it again this year from 5–9 p.m. on Thursday, December 4! Avoid the crowds (and long lines to see Santa at the Helen Brach Primate House) and enjoy free access to Ice Skating at Lincoln Park Zoo during your visit. Can’t make it December 4? Members will also have exclusive access to a members lounge on the lower level of Park Place Café on November 28–30, December 5–7 and December 12–31. Duck in to warm up with cookies, hot chocolate, cider and crafts!
Santa
Exclusive Animal Chats
Enjoy bite-size informal learning with zoo educators at members-only animal chats. Upcoming chats include: • Baby on Board: White-Cheeked Gibbons chat at 3 p.m. on Tuesdays, November 11 and December 9, at the Helen Brach Primate House. • Enrichment: Ways We Care African Lion chat at 3 p.m. on Saturday, November 29, at the Kovler Lion House. Chat sessions include 20 minutes of educator-led content followed by 10-plus minutes for members’ questions. Preregistration is recommended. Visit lpzoo.org/memberevents to register and see a full calendar of upcoming membership events.
Cock-A-Doodle Zoo!
More than 500 zoo members and their families rose with the roosters for Members-Only Morning at the Farm-in-the-Zoo on Saturday, September 13. The farm-themed fun included close-up encounters with barnyard animals, culinary workshops and craft making with organic treats from the Edible Garden. Stay tuned for the next Members-Only Morning in spring 2015!
Follow Us Online! Lincoln Park Zoo magazine isn’t the only way to stay up to date on the zoo’s world of wildlife. Connect with us on Facebook, Twitter, YouTube and the zoo blogs at www.lpzoo.org. New animal arrivals, special events, field reports by zoo scientists—they all await your discovery online.
Members-Only Night at ZooLights offers an exclusive opportunity to take in the holiday spectacle, including free ice skating for the evening. Our recent Members-Only Morning offered a fun look at life on the farm.
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Your membership supports everything we do, from animal care to publishing Lincoln Park Zoo magazine.
PO Box 14903 Chicago, IL 60614 www.lpzoo.org
Non-profit Organization U.S. Postage PAID Lincoln Park Zoo
Give the Gift of Wildlife
ADOPT an Animal at the zoo for a loved one this holiday! Our Baringo giraffe, Grevy’s zebra or African lion gift packages include a cuddly plush, personalized ADOPTion certificate, magnet-framed photo and fact sheet! The Holiday Experience ADOPT option adds vouchers for skate rental, ice time and hot chocolate at Ice Skating at Lincoln Park Zoo. Visit www.lpzoo.org/ADOPT for details.
Chicago Wildlife Watch
Help us ID animals in the Chicago area! The zoo has collected more than 1 million photos of local wildlife, from squirrels to skunks. Now we’ve partnered with Adler Planetarium to launch Chicago Wildlife Watch, a web-based project that lets you help researchers identify the species that call Chicago home. Visit www.chicagowildlifewatch.org to get started!
Facebook Fanfare
Lincoln Park Zoo’s Facebook page just zipped past 100,000 likes and shows no signs of slowing down. Not a fan yet? Find us on Facebook for the latest news on animals, events and learning adventures. And follow us on Twitter for our new #FromACurator updates.