CONTENTS

3 The Birth of an Indian Rhinoceros

8 Zoo News — Mammals

idea. 10 Zoo News — Birds

Friends of the National Zoo

National Zoological Park 12 Zoo Map

Washington, D.C. 20009 15 Zoo News — Reptiles and Amphibians

Bh ace: 17 ~The Viverrids

Executive Director and membership:

232-7700 7 S ff

Education and Volunteer Offices: OO ta

232-7703

Guided tours: 232-7703

Train tours: 232-7704

Window Shop: 232-7705

FONZ Board of Directors 1972-1973

Arthur Arundel, President

Montgomery S. Bradley, First Vice President

Lavell Merritt, Second Vice President

Stephen Hosmer, Treasurer

Joan L. Jewett, Secretary

Peter C. Andrews

Theodore Babbitt

Emanuel Boasberg

John S. Brown

Timothy V.A. Dillon

Ronald Field

Donna K. Grosvenor

Robert Mason

Isabel J. McDonnell

Shirley J}. McNair

Ruth N. Nelson

William N. Olinger

John B. Oliver

Nancy Porter

Gerald G. Wagner

Rosa M. Walker

~ Richardson White, Jr.

Executive Director

Sabin Robbins

Editor: Austin Hughes

Photograph on page 8 courtesy of Faulkner,

Fryer, and Vanderpool, Architects; photo on

page 9 by Naltchayan; all other photos by

Ray Faass.

Production by Monica Johansen.

THE ZOOGOER is published bi-monthly

and copyrighted © by Friends of the National

Zoo, c/o National Zoological Park, Washington,

D.C. 20009, second-class mailing permit

approved at Washington, D.C. Rate in the

United States $3 a year (of annual dues).

Dr. Theodore H. Reed, Director

Mr. Edward Kohn, Deputy Director

Mr. Warren J. Iliff, Assistant Director

Mr. John Perry, Assistant Director

Mr. Jaren Horsley, General Curator

Mr. Harold Egoscue, Curator (Mammals)

Mr. William Xanten, Curator (Mammals)

Mr. Guy Greenwell, Curator (Birds)

Mr. Larry Collins, Associate Curator (Mammals)

Mr. Miles Roberts, Assistant Curator (Mammals)

Mr. Michael Davenport, Assistant Curator

(Reptiles)

Dr. Clinton Gray, Veterinarian

Dr. Mitchell Bush, Veterinarian

Dr. Robert Sauer, Pathologist

Dr. John Eisenberg, Resident Scientist

Dr. Helmut Buechner, Senior Ecologist

Dr. Devra Kleiman, Reproductive Zoologist

Mr. Norm Melun, Architect

Mr. Emanuel Petrella, Chief, Buildings & Grounds

For information concerning the collection call

381-7283 or 381-7284.

For general visitor information call 381-7235.

Friends

the

National

The Friends of the National Zoo is a non-profit

organization of individuals and families who

frequently visit the National Zoo and who are

interested in supporting its growth and develop-

ment, particularly in the areas of education,

conservation, and scientific research.

As members of the Friends, you and your family

will be given benefits that will make your zoo-

going more enjoyable and educational.

For more information and a membership appli-

cation, please call 232-7700.

The Zoo’s newborn Indian rhinoceros with

his mother at the age of about two months when

he weighed 260 pounds—more than twice his

birth weight.

On January 30th, a male Indian rhinoceros

(Rhinoceros unicornis) was born at the

National Zoo’s Elephant House (number

17 on map)—the first live birth of this rare

and endangered species in the Western

Hemisphere and one of only about 20

births to have taken place in the world’s zoos.

In the wild there are less than 1,000 Indian

rhinoceroses still living in a few scattered

reserves in India and Nepal. The species’ range

was once much larger; as recently as the

Middle Ages it was widely distributed in the

northern half of the Indian subcontinent and

ranged as far east as Indochina. Its gradual

extermination was due to increased human

settlement and cultivation of the alluvial

plains that were its preferred habitat and to

the hunting of rhinos for the use of various

parts of their bodies—particularly the horn—

in magic and folk medicine.

The National Zoo’s adult male Indian

rhinoceros (‘‘Tarun’’) is 15 years old and has

been here since May of 1960; the female

(‘‘Rajkumari’”’) is ten years old and was received

in December 1963. Female Indian rhinoceroses

first enter breeding condition at the age of

about five years; consequently the Zoo’s

female was first placed with the male at that ag

in July, 1968, but no breeding took place.

There is an annual breeding season in the female

Indian rhinoceros, during which she comes into

estrus approximately every 46 to 48 days, with

each estrus period lasting about 24 hours. It

was found that Rajkumari’s breeding season

occurred in late summer and early fall each

year; and so, in subsequent years, she was

placed with the male during her apparent

periods of estrus at this time of year. Finally,

on September 30th, 1972, a mating occurred

that seemed to have been successful, the male

remaining mounted for an hour and ten minute

This mating pattern resembled that observed

in other successful captive breedings of Indian

rhinoceroses; and when the female’s next

scheduled estrus did not occur, it was con-

sidered a good indication that she was indeed

pregnant. Very gradually over the next year

the fetus increased in size, and by the fall

of 1973 Rajkumari’s pregnancy was obvious.

The gestation period of the Indian rhinoceros

had been measured, in the case of other

Captive animals, at between 462 and 489 days;

so, as the latter part of January, 1974,

approached, Zoo officials began to expect

the birth was imminent. A Friends of the

National Zoo “‘preg-watch”’ was organized to

keep watch on Rajkumari after Zoo hours and

to summon the veterinarian and other

relevant personnel in the event of a birth.

In fact, as it turned out, the birth took place

during Zoo working hours. But observers in

the early morning of January 30th were already

able to observe and record marked changes in

the female’s behavior that suggested that she

might well give birth that day; consequently the

Elephant House was kept closed to the public

on the 30th. From midnight until 6:30 a.m.

Rajkumari had been extremely restless. She

would lie down and then rise to her feet

immediately. She whistled frequently, another

The Indian rhinoceros has three toes on each foot,

and each toe bears a hoof. These toes are descended

from the second, third, and fourth of the five

toes the ancestors of all mammals had.

sign of an excited state; this vocalization of

the Indian rhinoceros occurs only rarely, the

circumstances under which it is most commonly

observed being when the female is in estrus.

Later in the morning, she could be seen

running around her cage and lashing her tail.

At approximately 2:00 p.m. Rajkumari lay

down and rolled over, almost onto her back;

then she stood up again, and delivery

immediately began. The calf’s front hoofs,

ivory in color, could be seen through the

pink birth membrane, protruding from the

mother’s vulva. After several minutes, during

which Zoo officials watched anxiously

through peep-holes cut in the black canvass

that covered the front of her cage, the

mother lay down on her right side, then

rose again, and then again lay down,

this time on her left side. At this point

the birth membrane was broken. The female

stood up again, moved in a half circle, then

circled around fully, lashing her tail; and

when she stopped the calf was dropped to

the straw-covered floor of the cage. The

birth apparently took place with head

and forelegs emerging first, and the mother

gave a short, soft whistle as it was happening.

The entire process of delivery had lasted

only about 20 minutes.

The calf lay on its side, its chest heaving,

and the mother sniffed it before lying

down beside it. It was observed that the

newborn was a male, and the announcement

was made soon afterwards that he would be

named “‘Patrick”’ in honor of the United

States ambassador to India, Daniel Patrick

Moynihan. It was about an hour and a half

after the birth that Patrick first stood up.

As he lay, his mother would occasionally

nibble at his hoofs, perhaps in an effort

to stir him up. She also occasionally felt the

infant’s head and feet with her sensitive

hooked upper lip.

The mother showed an interesting behavior

pattern during this time—the exaggerated

curl of the upper lip known by the German

word Flehmen. In Flenmen—which appears

in a number of other hoofed mammals

besides the Indian rhinoceros—the animal

is bringing scent to an organ in the roof of

the mouth known as Jacobson’s organ.

Jacobson’s organ is an organ of smell, supple-

mentary to the ordinary channels of smell

in the nose and presumably more sensitive,

at least to certain types of odor. Adult male

Indian rhinoceroses use Flehmen to bring

to Jacobson’s organ the scent of the female’s

urine when she is in estrus; evidently

Jacobson’s organ is sensitive to the particular

chemical composition the female’s urine

assumes when she is in estrus. Rajkumari

was perhaps using the same organ to familiarize

herself with her offspring’s scent, which

may be important for the mother’s

recognition of her offspring in the evidently

rather nearsighted rhinoceros.

Before standing up for the first time, Patrick

occasionally made struggling movements; when

he finally did stand, his mother was also

standing and he attempted to locate her

teats. He kept circling behind her, so that

she had to block him with one of her hind

legs to prevent his going behind her.

Apparently, while the infant had an innate

tendency to circle around towards his mother’s

rear, he had no innate knowledge of the exact

location of the udder. When he did locate the

udder, smell may have been the most important

sense in leading him to it.

The baby rhinoceros had a smooth, flat oval

area on his head where his horn would later

grow. The horn of the rhinoceros is made

entirely of keratinous material—one of the

group of allied substances that constitute

the claws, hoofs, nails, and hair of mammals,

as well as the feathers of birds and the scales

of reptiles. Unlike the horns of cattle, antelope,

and their relatives, which consist of a

keratinous sheath covering a bony core, the

horn of the rhinoceros contains no bone and

consists entirely of keratin. All keratinous

substances are non-living but are produced

from the living matter of the animal’s skin;

and, as Patrick’s horn grows keratin will be

produced by his skin and added to it.

Patrick was weighed on the second day of his

life, and the 125 pounds at which he registered

then was believed to be close to his birth

weight; birth weights of other young of this

species have varied between about 75 and

150 pounds. By the time he was one day old

he was already running playfully around his

cage. Like other young Indian rhinoceroses,

Patrick gained weight rapidly. In the first week

of life he gained an average of 5.3 pounds per

day and had attained a weight of 162 pounds

by the end of that period. When next weighed,

on February 15th, Patrick weighed 196

pounds; and he weighed 261 pounds on March

Ist, having thus already more than doubled

his weight in the first month of his life. As

an adult he may weigh more than two tons.

Young Indian rhinoceroses nurse until the

age of about sixteen months, although

gradually learning to eat solid food during

that time. In the wild it is believed that Indian

rhinoceroses maintain small matriarchal

groups, each consisting of an old breeding

female, several of his previous offspring, and,

if these are females, perhaps their offspring.

How long a male calf stays with such a group

is not known, but it is certain that by the time

he reaches sexual maturity at the age of nine

years he is solitary. In captivity, however, a

male offspring could not be kept with his

mother anywhere near such a long time, and

he would most likely be separated from her

shortly after weaning.

Exactly what is in store for Patrick in the future

is uncertain. Obviously the first priority will

be to pair him up with a female Indian

rhinoceros for breeding as soon as he is

sexually mature. This may mean that he

will be sent to another zoo, at least for a

time. Another factor that may eventually in-

fluence Patrick’s future is the National Zoo’s

recent acquisition of the use of an off-exhibit

breeding farm. A former U.S. Department of

Agriculture research station located near Front

The area on Patrick’s head where his single

horn is beginning to grow.

Royal, Virginia, the farm will hopefully in

the future provide facilities for breeding rare

species in numbers greater than are allowed

for by the limited space available in a city

Z00; and it Is possible that sometime in the

future the Indian rhinoceros may be among

the species bred there.

ZCONEMS

Mammals

Lion and Tiger Exhibit Construction

Demolition of the Lion House (number 23 on

map), the oldest animal exhibit building at the

Zoo, is now complete; built in 1891 to house

all animals requiring heated quarters in

winter, the Lion House will be replaced by

spacious modern enclosures to display large

cats. There will be two enclosures for tigers

and one for lions, each containing rocks for

climbing, trees, heated grottos, and water-

courses. The entire complex will be surrounded

by a water moat so that visitors will be able

to view the animals without obstruction,

and the individual enclosures will be separated

Architect’s model of the Zoo’s future

Lion and Tiger Complex, construction of

which is expected to be completed by the

Bicentennial Year.

from each other by dry moats. The complex

will cover all of the current Lion House Hill.

There will be indoor winter enclosures sunk

below the ground, with indoor viewing for

the public; this is in keeping with the goal

of the Zoo’s Master Plan to minimize the

impact of man-made structures on the land-

scape of the Park.

As most readers will already be aware, some

of the occupants of the Lion House, including

the Zoo’s famous white tigers and the

Zoo's normally colored Bengal tigers, have

been sent to other zoos for the duration of the

construction. Other animals that formerly

lived in the building and in enclosures behind

the building have either been shipped to

other zoos or relocated in other enclosures

here. The jaguars and siamang gibbons, for

instance, have been moved to temporary

“corn-crib” cages (number 29 on map),

and the Matschie’s tree kangaroos group has

been moved to the Reptile House (number 19

on map). The cheetahs are not currently on

exhibit, but a large new yard is being con-

structed for them on the hillside next to

the current tapir yard (number 26 on map).

FONZ panda-watchers could observe

nocturnal behavior such as this; the results

of their watches helped Zoo scientists

form a picture of the panda’s nocturnal activity.

Giant Panda Watch

Between April 1st and 7th, Friends of the

National Zoo volunteers kept records of the

nocturnal activities of the giant pandas; the

principal aim of the watch was to discover

what if any changes had taken place since

previous watches had given Zoo scientists an

idea of how the pandas were spending their

time after Zoo closing. It was immediately

apparent that both animals are now sleeping

more at night than they did previously; it

had been expected that this would happen

as the pandas grew older. As was not the

case on previous watches, the male (‘‘Hsing-

Hsing’’) now showed almost no play behavior

at night, but the female did play, mainly in

the early morning. The male fed mainly

between 5 and 7 PM and again between 7 and

11 PM; the female fed mainly between 1 and

3 AM, although she nibbled intermittently

between 5 and 9 PM.

The most noticeable changes seemed to be

attributable to the fact that the pandas’ new

cages are fully separated from each other,

whereas their previous cages were connected

by alocked door. The two pandas were now

found to scent-mark with equal frequency—

a dramatic change since Hsing-Hsing had

previously scent-marked far more frequently

than Ling-Ling. Previously Hsing-Hsing

had frequently marked the door dividing the

two cages, and the fact that he can no longer

use his scent-glands to interact with the

female may be the reason for his decreased

marking. The pair seemed less synchronized

in their activity than they were on previous

watches—probably another effect of their

separation.

Birds

White-Necked Rock Fowl Nesting

Since 1971 the National Zoo has been

attempting to breed the white-necked rock

fowl (Picathartes gvmnocephalus), and now

success seems within reach. A pair has built

an impressive nest platform attached to

the wall of their cage at the rear of the Bird

House (number 5 on map), and a single egg

was laid in early April. This species, native.

to Sierra Leone, Ghana, and Togo, is apparently

quite rare and possibly in danger of extinction;

it has rarely been bred successfully in captivity.

Captive breeding has been difficult for a

number of reasons. First there is no apparent

external difference between the sexes; and,

since the species’ behavior is little known,

no behavioral clues appear to have as yet

been discovered on the basis of which it might

be possible for an observer to distinguish

males from females. In addition, even when

a zoo does have a true pair, their exact

requirements for successful nesting are only

beginning to be understood. In fact our

knowledge of all aspects of the white-necked

rock fowl’s biology is fragmentary.

This lack of knowledge extends even to the

species’ taxonomic position. Currently most

ornithologists place the white-necked rock

fowl and its only known close relative, the

gray-necked rock fowl (Picathartes oreas),

with a family of Old World birds known as

the babblers (the Timaliidae). But some are

uncertain whether the babblers themselves

represent a natural assemblage of truly related

species or an artificial conglomeration of

species only assumed to be related by exas-

perated systematists. A good example of a

babbler is the arrow-marked babbler (7urdoides

jardineii) that shares the white-necked rock

fowls’ cage at the Bird House. The resemblance

between the two species’ method of locomotion

will immediately be apparent; both tend to

move along the ground by long hops, propelled

by their powerful legs and occasionally

assisted by spreading the wings. But in other

respects the rock-fowl are less babbler-like.

For instance, as the name implies, the babblers

are generally highly vocal birds; but the

white-necked rock fowl has never been heard

uttering any other sound besides a rather soft

monosyllabic croak.

The white-necked rock fowl is mainly terrestrial,

searching forest floors for a diet that is said

to include insects, small frogs, crustaceans,

and snails. In captivity they have proved

themselves capable of killing other birds and

mice and will also take fruit. It is reported that

they are gregarious in the wild and that they nest

on cliffs; but whether they are colonial nesters

in the sense that pairs nest in close proximity

of each other does not seem to be definitely

established. In captivity no more than one pair

has nested per cage, even in relatively large

cages.

In cases of successful captive breeding some

sort of elevated platform has served as a

substitute for a cliff ledge. in the wild the nests

are said to be made of mud and plant fibres.

The Zoo’s pair has been provided with a pan

of wet clay and hairs for fibres, and they

have used these materials readily, rolling the

clay into balls with their bills before taking it

up to the nest platform. The members of the

pair can be distinguished by the fact that one

has no color-band, while the other has a red

color-band on its left leg; there is one other

white-necked rock fowl in the cage, which

has a white color-band on its left leg. When

one member of the pair relieved the other at

work on the nest, it usually hopped to the

top of the rock pile at the rear of the cage and

looked up until the other bird flew down.

Interestingly, the third bird in the cage spent

some time building a ‘‘nest’”’ of its own—at

ground level in the front right corner of the

cage.

Both members of the Zoo’s pair have been

taking turns incubating; and when one relieves

the other it usually brings some nesting

materials—soil or fibres—with it in its bill, so

that the nest is increasing in size while the

egg is being incubated. The bird on the nest

may greet its approaching mate with a soft

croak before leaving the nest so that the

other bird can take over.

Young of this species remain in the nest three

to four weeks after hatching; when they are

fledged they resemble their parents except that

they have shorter tails and the bare yellow

skin on their heads is paler. One of the

‘greatest mysteries about the white-necked

rock fowl, incidentally, is the unusual

coloration of the head. The feathers of the back

and wings are black, and those of the breast and

neck are white; but the head is without feathers,

yellow in color except for two large black spots

on either side. Observations at the National

Zoo suggest that these spots function as social times one white-necked rock fow! will turn

signals; indeed it is to be expected that a its head so as to display one of these spots to

species that is presumably social and yet almost another white-necked rock fowl, and it may

without vocalizations should have some sort be that the spot serves to inhibit aggression

of visual means of social communication. Some- on the part of the bird to which it is displayed.

White-necked rock fowl on its nest at

the Bird House (number 5 on map).

: 12. Water birds (a-e)

13. Hawks and owls (a-c)

14. Black Rhinoceros Yard

15. Small Mammal Building

1. Connecticut Avenue pedestrian entrance 16. Lesser Pandas

2. Connecticut Avenue vehicular entrance 17. Prairie dogs

3. Deer and antelope areas (a-j) 18. Bears and monkeys (a-m)

4. Great Flight Cage 19. Reptile House

5. Bird House 20. Tortoise yard

6. Pheasant and crane line (a-u) 21. Monkey House (under construction)

7. Raptor cages (a-d) 22. Lion and Tiger Exhibit (under construction)

8. Delicate-hoofed stock building (a-c) 23. Komodo Dragon

9. Hardy-hoofed stock complex (a-i) 24. Bears (a-j)

10. Panda House (a-c) 25. Water animals (a-e)

11. Elephant House 7 26. Sea Lion pool

. Jaguars and Siamang gibbons (a-b)

. Waterfowl ponds (a-d)

. Police Station—Restrooms—First Aid

. Restaurant

. Picnic Area

. Window Shop

. Souvenir Kiosk

. Rock Creek Parkway entrance

. Friends of the National Zoo Education Office

. FONZ Membership and Editorial Offices

Telephone

Restrooms

Trackless Train Stops

Parking

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——— »Walking Tour Route

(From the Trackless Train

Stations)

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12. Water birds (a-e) 27. Jaguars and Siamang gibbons (a-b) _ ae Telephone

13. Hawks and owls (a-c) 28. Waterfowl! ponds (a-d) |

14. Black Rhinoceros Yard | 29. Police Station—Restrooms—First Aid b0 Restrooms

15. Small Mammal Building 30. Restaurant

1. Connecticut Avenue pedestrian entrance 16. Lesser Pandas 31. Picnic Area ;

2. Connecticut Avenue vehicular entrance 17. Prairie dogs 32. Window Shop * eee sila

3. Deer and antelope areas (a-}) 18. Bears and monkeys (a-m) 33. Souvenir Kiosk fillies

4. Great Flight Cage 19. Reptile House 34. Rock Creek Parkway entrance oe AER eg

9. Bird House — 20. Tortoise yard A 35. Friends of the National Zoo Education Office fae

6. Pheasant and crane line (a-u) 21. Monkey House (under construction) | 36. FONZ Membership and Editorial Offices

7. Raptor cages (a-d) 22. Lion and Tiger Exhibit (under construction) — i ee

8. Delicate-hoofed stock building (a-c) 23. Komodo Dragon [ f‘Erom the Trackless Train

9. Hardy-hoofed stock complex (a-i) 24. Bears (a-j) Stations)

10. Panda House (a-c) 25. Water animals (a-e)

11. Elephant House 26. Sea Lion pool

12 | 13

California Quail

One of the most beautiful of the North

American quail is the California quail

(Callipepla californica), a pair of which has

recently been placed on exhibit at the Bird

House (number 5 on map), in a cage directly

to the right of the flamingo cage. The California

quail ranges from southern British Columbia

to the tip of Baja California; originally it did

not range north of southern Oregon, but

human introductions have spread it farther

to the north. Eight subspecies are recognized.

The one to which the Zoo’s pair belongs ts

known as the valley quail (Ca//ipepla

californica californica); it was originally

distributed throughout California and western

Nevada and is the subspecies that has been

introduced to the north.

The most striking feature of the California

quail is the forward-directed teardrop-shaped

crest. As in most quail species, the females are

duller in appearance than the males, the black

throat being the most apparent distinguishing

mark of the male. Both sexes are basically

gray in color, with buffy feathers on the

abdomen that are fringed with darker markings

giving them a “‘scaly’’ appearance.

In the wild the sexes live together in mixed

covies from late fall until early spring. In spring

hormonal changes occur in the males, brought

about by increasing day-length; these in turn

spur the males to increasing aggressiveness

against each other. This leads to the break-up

of the covies and the formation of breeding

pairs. Each pair is not territorial in the sense

of defending a specific piece of habitat against

other pairs. Territoriality appears only in males

that, in March and June when most pairs have

_ been formed, are still without mates. Breeding

pairs are quite limited in their movements,

however; when the female is incubating her eggs,

the members of the pair rarely stray beyond an

area of some three to ten acres in area around

the nest.

The California quail’s nest is a depression

scraped in the ground and usually lined with

some sort of plant litter. The average

number of eggs is 14, which are laid over a

period of about 22 days. Incubation usually

takes 23 days. As in other quail, whose

terrestrial habitat entails a high degree of

predation, the large clutch size is an

adaptation to high chick mortality. In one

California study, it was found that over-all

about three young per breeding female

were raised each year.

Like all quail the California quail feeds on

both plant and animal food; however, the

percentage of animal food in the diet is

relatively low in this species. For example,

in summer when insects and other invertebrates

are most abundant, they may make up 30

percent of the diet of the familiar bobwhite

quail (Colinus virginianus). \n the California

quail by contrast such animal food makes

up only about 5 percent of the summer diet,

and most of the species’ food consists of

the leaves of weedy herbs and their seeds.

Male California quail (Ca//ipepla californica).

Burmese Pythons Incubating Eggs

At this writing two female Burmese pythons

(Python molurus bivittatus) are incubating

clutches of eggs in cages E-8 at the Reptile

House (number 19 on map). Each female

remains coiled about her eggs while incubating

them, not eating and only drinking water

occasionally, while frequent spasmodic

muscular contractions raise her body temper-

ature in order to provide extra heat to the

eggs. Thermometers have been placed within

each female’s coils so that keepers can

monitor the heat produced.

Reptiles, it should be remembered, are

“cold-blooded”’; or, more properly they are

Female Burmese python coiled about her eggs;

the wires connect with temperature-measuring

devices which monitor the heat

produced by the incubating female.

poikilothermic—having a quite variable body

temperature—and ectothermic—depending

on heat from their environment. In other words,

unlike those of birds and mammals, their

metabolic processes do not in themselves

produce enough heat to raise their body

temperatures to the level required for the

animal to perform essential activities;

reptiles are thus largely dependent on

external sources to obtain this needed heat.

Most often when a reptile needs to influence

its body temperature it does so behaviorally.

A snake, for example, may bask in the sun

till its body temperature is raised to the

optimum and then withdraw to the shade.

The incubating Burmese python’s ability

to raise her body temperature by muscular

contractions is one of very few cases where

a reptile can significantly influence its body

temperature by internal heat production.

It has been reported that by these contractions

the Burmese python is able to raise her body

temperature as much as 13 degrees Fahrenheit

above the temperature of the surrounding air.

Vertebrate embryos need heat in order to

develop. Birds provide this heat from their

own ‘‘warm-blooded”’ bodies when incubating

eggs; most mammals provide it by retaining

the embryo within the mother’s body. Most

reptile eggs are dependent on environmental

heat, so that the time it takes them to develop

to the point where they are ready to hatch

varies greatly not only from species to species

as with birds’ eggs but within species from

year to year and from place to place, depending

on environmental conditions. The incubating

behavior of the Burmese python thus

introduces some control on this variability.

One of the Zoo’s two incubating females laid

a clutch estimated at between 20 and 24

eggs on February 24th; the other laid a clutch

of 46 eggs (14 of which were removed for

artificial incubation) on March 5th. The

incubation will take about 65 days in each case;

after hatching the young will be removed

from the cage, as in the wild they would

immediately disperse themselves from the

mother.

Poison-Arrow Frogs

Four species of frogs from Panama known as

poison-arrow frogs have recently been acquired

by the Reptile Unit. The species belong to

two related genera, Dendrobates and

Phyllobates, found only in tropical America;

the former genus contains about ten species,

the latter about twenty species. Like many frogs

and toads, these frogs have poisonous skin

secretions, and their collective English name

derives from the fact that the secretions of some

of these species are used by Indians to tip their

arrows. Evidently the frog is held over a fire,

and the heat causes the poison to be exuded

onto the arrow tip. These small frogs, like many

other poisonous species, are quite brilliantly

colored, as the four species at the Zoo illustrate.

Dendrobates pumilio has a bright red back

with small black spots on it and black legs;

Dendrobates granuliferus has a red back

and green legs; Dendrobates auratus is green

with black spots; and Phy/lobates lugubris

has a black back with two bright yellow

longitudinal stripes on it and green legs.

Aside from their use by man, the poison-arrow

frogs are also noteworthy for their life

history. It is known of a number of species

of poison-arrow frogs, and may be true of

all, that the male exhibits a unique form of

parental care. In Dendrobates auratus, the

female lays from one to six eggs surrounded

by an irregular mass of sticky material; this

material provides needed moisture for the

eggs, which, unlike those of the most familiar

frog species, are laid on land. The male remains

in the vicinity of the eggs, either standing by

and guarding them or visiting them

periodically. When after about two weeks,

the eggs hatch, the tadpoles wriggle onto the

male’s back. He then carries them to water,

where they live the typical aquatic life

of frog tadpoles until approximately six

weeks later when they metamorphose into

adults.

Poison-arrow frog (Phy/lobates lugubris).

The name viverrid (the accent is usually placed

on the second syllable) will probably not be a

familiar one to most readers; nor are the

members of the family of mammals to which

it refers—the civets, genets, mongooses, and

their relatives—familiar to most inhabitants of

North America. The major reason for this is

doubtless that this family, known to scientists

as the Viverridae, though very widespread in the

Old World, particularly in the Old World tropics,

does not occur naturally in our Hemisphere.

(A species of mongoose has been introduced

by man to the West Indies and to Hawaii, with

disastrous results for native wildlife.) Related

families—the other families in the order _

Carnivora or carnivores to which the viverrids

belong—are among the most familiar of

mammals, including as they do the bears,

cats, and dogs. Yet there are more species in

the viverrid family—seventy-one—than are

found in any other family in the order

Thirteen of these species are on exhibit at the

National Zoo’s Small Mammal House (number

15 on map). But perhaps few visitors there

realize that these animals—most of them rather

like small cats or weasels in appearance—are all

of one family, or that the National Zoo is

privileged to maintain one of the most

numerous and representative collections of

viverrids anywhere in captivity.

Present-day carnivores are divided into two

great groups or suborders—the dog-like

carnivores (Canoidea) and the cat-like carni-

vores (Feloidea). Both of these groups

derive from a common origin, but they began

to follow different evolutionary courses in

the distant past; probably the dog-like

carnivores had their main center of evolution

and diversification in the Northern Hemisphere

_ of both New and Old Worlds, while the cat-like

carnivores had theirs in the Southern

Hemisphere of the Old World. Today the

dog-like carnivores include not only the dog

family, but also the closely related bear

family, the weasels and their relatives,

the racoons and their relatives, and the pandas.

The living cat-like carnivores consist of three

families: the viverrids, the hyenas, and the cats.

Both the cats and the hyenas are descended

from early viverrid stock.

The ancestors of both the dog-like carnivores

and the cat-like carnivores belonged to a

long-extinct carnivore family known as the

<Page 17 Vontsira or Madagascar ring-tailed mongoose

(Galidia elegans).

miacids, which flourished some 35 million

years ago. From fossil remains we know that

these were small-to-medium-sized animals,

and we can even guess something about their

way of life from the details of their skeletal

structure and—in particular—the structure

of their teeth. The miacid skeleton suggests

that these carnivores were arboreal; the teeth

suggest that, while definitely predatory, they

were by no means exclusively meat-eaters

but relied on a mixed diet that included

considerable amounts of plant food and

perhaps insects.

The miacid carnivores were characterized by

an important dental innovation for feeding

on meat; this was the development of the

so-called carnassial teeth as flesh-cutting

shears. The carnassials are the last premolar

in the upper jaw and the first molar in the

lower jaw, and in the miacids they developed

into blades that sheared past each other

with a somewhat scissor-like action when

the jaws were closed. In most present-day

carnivores the carnassial teeth have retained

this shearing function. When a dog, for

instance, chews sideways at a bone, the

carnassials are being used to slice meat from

the bone. The carnassials can also be used

to cut through tendons in the prey carcass

and to slice meat into chunks small enough

to swallow.

In the miacids the carnassials had not

developed the shearing function to the extent

that they were to develop it in some later

carnivores—most notably the cats, which are

the most purely meat-eating of all carnivores.

That the miacids had a mixed diet can be

inferred from this and from one other aspect of

their dentition—the presence of relatively

robust molars for grinding plant food. Many

modern carnivores have teeth similar to those

of the miacids, including many of the

viverrids. In fact, many of the viverrids—in

dentition, in size, in over-all body structure,

and presumably in habits—have departed

less from the ancestral miacids than have any

other living carnivores. Most of the viverrids,

too, are mixed feeders. They generally prey

on small vertebrates but also take substantial

amounts of plant food and some insects; they

are predators but are by no means specialized

as exclusive predators. Typically they have both

fairly well-developed carnassials and also two

molars on each side of both upper and lower

jaws; and each of these molars, except for the

molar involved in the carnassial shear, is fairly

well adapted for plant-crushing purposes.

In the cats, by contrast, the molars are greatly specialized and exclusive predators that have

degenerated. On each side of a typical cat’s ever evolved among the mammals. That this

mouth, the one lower molar involved in the is true of a lion or a tiger will probably come

carnassial shear and one degenerate upper as no surprise to anyone, but the realization

molar are the only molars that have remained, Should also increase our respect for the

The premolars too are reduced in number. domestic cat.

As this dentition would lead us to expect, the

cats are more highly specialized as predators The difference between the unspecialized

and as meat-eaters than any other carnivores; viverrid and the highly specialized cat can

they are, in fact, as a group the most highly readily be inferred from a comparison of the

Common Asiatic palm civet (Paradoxurus

hermaphroditus), a viverrid species whose diet

includes a relatively large percentage of fruit.

It is also apparently fond of palm sap tapped by

man for making palm wine or “‘toddy’”’ and

has earned the vernacular name “‘toddy cat.”

As with many of the viverrids, its large eyes

are indicative of nocturnal habits.

African water mongoose or march mongoose

(Atilax paludinosus), an excellent swimmer and

one of few semi-aquatic viverrids.

well known profile of a cat with the profile of

a typical viverrid mixed feeder at the Small

Mammal House, for example the lesser

oriental civet (Viverridula indica). The civet

must accommodate functioning molars as

well as more premolars than a cat has, and

consequently its skull is noticeably more

elongated. The cat’s more rounded skull,

on the other hand, concentrates fare more

of the muscular power of the bite on the

‘cutting action of the carnassials.

The fact that the majority of viverrids have not

specialized as regards diet has allowed them to

fill a wide variety of ecological niches. There are

highly arboreal species, purely terrestrial species,

and species at home both on the ground and in

the trees; species of the tropical forest, species

of the open grassland, and even semi-aquatic

species; nocturnal species and diurnal species;

solitary species and social species. Much of this

diversity is illustrated by the collection at the

Small Mammal House (See box, page 21).

The lesser oriental civet is a good example of

a mainly terrestrial viverrid with a mixed

diet. It feeds to a considerable extent on

roots and fallen fruits, also eats insects and

their larvae, and captures small mammals. The

masked palm civet (Paguma /arvata) is an

example of an arboreal mixed feeder. The

African palm civet or two-spotted palm

civet (Nandinia binotata) and the common

Asiatic palm civet (Paradoxurus hermaphroditus)

are mixed-feeding species in which vegetable

food—especially fruit—has evidently come to

make up a larger portion of the diet than

in most mixed feeders. The former species,

despite its heavy reliance on fruit, is reportedly

able to kill some surprisingly large prey—

for example the primitive primates known as

pottos. The large-spotted genet (Genetta

tigrina) is a mixed feeder that has come to be

more predacious and less vegetarian than

many others; and its molars, although two tn

number on each side of both upper and

lower jaws, are correspondingly reduced in

size.

There are a few outstanding exceptions to

the unspecialized mixed-feeding habits that

are typical of the viverrids. One species that

appears to have lost most prey-catching

ability and become almost exclusively

vegetarian is the binturong (Arctictis binturong),

which is evidently the most heavily vegetarian

predacious of the viverrids. The cats never

reached Madagascar, which was separated from

the mainland before they had come into

existence; but the fossa has taken the place of

a medium-sized cat to a considerable extent

and has come to resemble the cats more than

any other viverrid, both in over-all appearance

and in dentition. Like the cats the fossa has

only one degenerate upper molar on each

side of the mouth and has a reduced number of

premolars; thus its teeth have lost virtually

all plant-crushing usefulness. The carnassials

are very well developed as shears. There is no

evidence that the fossa represents a ‘‘missing

link’? between the cats and viverrids; but the

ancestors of cats, as they diverged from the

of all the viverrids. It is arboreal and quite slow

moving, seemingly incapable of the active

pursuit of most living vertebrate prey; and

its carnassial teeth have become ‘‘molarized”—

‘in other words, they have lost their shearing

function in favor of a plant-crushing function.

The only meat that is regularly consumed ts

probably carrion, although when it does

happen upon some small prey that it is able

to capture, the binturong doubtless takes

advantage of the opportunity.

The position of the fossa (Cryptoprocta ferox)

is unique. It is the largest native carnivore on

Madagascar and the most truly and exclusively

SPECIES OF VIVERRID AT THE NATIONAL ZOOLOGICAL PARK

SPECIES

Large-spotted genet

(Genetta tigrina)

RANGE

Africa south of the

Sahara

India, Southeast

Asia

Lesser oriental civet

(Viverricula indica)

Malaysia, Sumatra,

Java, Borneo

West and Central

Africa

Banded linsang

(Prionodon linsang)

African palm civet

or two-spotted palm

civet (Nandinia

binotata)

Southeast Asia,

Indonesia,

Philippines

Common Asiatic

palm civet

(Paradoxurus

hermaphroditus)

China, Southeast

Asia, Sumatra,

Borneo

Southeast Asia,

Masked palm civet

(Paguma /arvata)

Binturong

(Arctictis binturong)

Fanaloka (Fossa Madagascar

fossa)

Malaysia, Sumatra,

Borneo

Banded palm civet

(Hemigalus derbyanus)

Vontsira

(Galidia elegans)

Madagascar

Africa south of

Sahara

Water mongoose

or marsh mongoose

(Atilax paludinosus)

Black-footed

mongoose (Bdeogale

nigripes)

West Africa

Fossa (Cryptoprocta Madagascar

ferox)

HABITS

nocturnal; terrestrial

and arboreal

nocturnal; terrestrial

and arboreal

nocturnal; mainly

arboreal

nocturnal; mainly

arboreal

nocturnal; highly

arboreal

nocturnal; mainly

arboreal

nocturnal; highly

Sumatra, Java, Borneo arboreal

nocturnal; terrestrial

poorly known

diurnal; both

arboreal and

terrestrial

diurnal; semi-aquatic

diurnal and

terrestrial

poorly known

DIET

one of the more preda-

cious species: small

mammals, birds, lizards,

and insects

mixed; small mammals,

birds, insects, fruit,

and roots

mixed

a large percentage of

fruit, but also some

vertebrate prey and

insects

a large percentage of

fruit, but also small

vertebrates and insects

mixed: small vertebrates,

fruit, roots, and insects

mainly fruit; carrion

mixed: fruit, insects,

small mammals, and

lizards

poorly known; perhaps

mainly fruit and insects

and other invertebrates

poorly known

frogs and aquatic

crustaceans; small

mammals; some fruit

predominately vegetable;

some insects and small

vertebrates

highly predacious

The fossa (Cryptoprocta ferox) is the most

predacious of the viverrids and the largest native

carnivore on Madagascar.

viverrid stock, may have passed through a stage

at which they closely resembled the fossa.

Nothing seems to be known of the manner in

which the fossa kills its prey in the wild, but

comparisons of the killing methods of some

of the viverrids with those of cats of similar

size are instructive. When a small cat kills a

small mammal, it usually pounces on and

stops the prey with its forepaws, and then a

single swift bite of the cat’s long canines

separates two neck vertebrae near the base

of the prey’s skull, severing the spinal cord and

causing almost instant death. (The methods

used by the larger cats, which often kill prey

significantly larger than themselves, are at

times rather different.) The ability to orient

the bite with such amazing accuracy is unique to

the cats and is the major reason for their

high reputation as efficient predators. The

less skilled viverrids have never evolved the

ability to administer so swift and direct a

coup-de-grace. A civet or genet, for instance,

may kill with repeated bites to the neck of

the prey. These may be given very quickly,

without the predator’s every fully withdrawing

its teeth. In this case the only visible wounds

may be four punctures where the upper and

lower canines entered, but beneath the skin

flesh and bone are severely mauled. The

spinal cord is severed, but by a more random

method than that used by a cat. A civet or

a genet may also at times be unable to take

hold of the neck of the prey with its first

bite and may, by biting several times and fully

withdrawing the teeth after each bite, shift

the bite to a position in which it will be lethal.

Aside from the foods already mentioned, a

great many viverrids readily take birds’ eggs;

and a number of species have evolved

interesting ways of breaking eggs and other

hard-shelled objects. Some mongooses will

hold an egg between the forepaws and, standing

up on the hind legs, throw it backwards

between the legs like a football center in

order to smash it against a rock or a tree trunk.

The water mongoose uses a somewhat different

behavior pattern; rearing up on its hind legs,

it hurls the eggs downward to the ground.

One captive water mongoose could do this

with sufficient force to shatter a nut, and it

is possible that in the wild the water mongoose

uses this method to break open shellfish.

Tame mongooses have amused their owners by

trying out these behavior patterns on such

man-made objects as‘ping-pong balls.

One of the most interesting aspects of the

viverrids’ biology is the high degree to which

scent-producing glands have evolved in this

family. Indeed it is difficult for us to realize,

visually oriented as we are, how large a role the

sense of smell plays in virtually every aspect of

these animals’ lives. Most are nocturnal, and

even diurnal species must often search for prey

in dense underbrush; in either case smell and

hearing are the most important senses guiding

the predator. So it is not surprising that the

viverrids, and the other carnivores, have come

to rely on scents in their communication

with one another and have often evolved

specialized glands for the purpose of

communication by scent.

Another reason that scent has come to play a

large role in intraspecific communication among

the viverrids is that most viverrids, like most

predators, are solitary animals. The limited

amount of available prey necessitates a

solitary, territorial lifestyle for all but a few

predators; each animal must be assured of

an individual territory on which no others

of the same species will trespass, a territory

large enough and well enough stocked with

prey to support the territory holder. Scent,

because it can be deposited at various points

on the boundaries of the territory and within

the territory and because it is recognizable

-at night when visible clues would not be, provides

-an ideal method of territorial demarcation, an

enduring warning to would-be trespassers..

One difficulty posed by a solitary life-style is

that some means must evolve to enable the

sexes to come together for mating, and here

_again scent can play a role.

_A number of different kinds of scent glands are

found in the viverrids, producing the odors

_used in intraspecific communication—odors

that are much in evidence at the Small Mammal

House. The two most common types of

_viverrid scent glands are located in the

anogenital region; these are known as the anal

sacs and the perineal glands. The anal sacs are

Said to be present in all, or almost all,

_Carnivores, although they are vestigial and non-

functioning in some, such as the bears and the

otters. The anal sacs are paired, one opening on

either side of the anus. The perineal gland—also

_known as the ‘‘perfume gland’’—is located

_ between the anus and the external genitalia

and is unique to the viverrids; it is absent

_in the mongooses and the fossa. The perineal

gland may be a simple patch of glandular

tissue, but in some species there are folds of

Skin on either side of this gland that form storage

pockets for its secretion.

The perineal gland secretions of certain Asiatic.

Civets are collected by man for use as perfumes;

the lesser oriental civet is one of these species.

The animals are kept in cages, and the secretion

of the gland is periodically scraped out of the

“Storage pockets with a spoon-like implement.

Neither particularly pleasant nor particularly

‘unpleasant to humans in the quantities in which

it is applied during the civet’s own scent-

marking, the odor has evidently proved

pleasing to man in more minute quantities. It

is used to scent some Indian tobaccos and has

long been prized in perfumery. Shakespeare

remarks in Much Ado About Nothing that if

a young man “rubs himself with civet ... the

‘sweet youth’s in love.’’ It is interesting to note

that, while civilized Western man has come

to show an aversion to the sexually attractant

Odors provided him by his own biology

(particularly those produced by the apocrene

‘sweat gland of the armpit), he has willingly

teplaced them with odors that have evolved

to play a similar attractant role in other species,

as well as with a variety of other natural

_and artificial odors.

The viverrids use a number of different postures

“when marking with the anal and perineal

glands. One of these is a handstand technique

used to bring the anogenital region in contact

with a vertical surface. Among species at the

Zoo, the water mongoose uses this posture

to mark with the anal sacs, while the large-spotted

genet uses it to mark with the perineal

glands. Other species, including the lesser

oriental civet, simply back into a vertical

object to mark it. Some species mark a

horizontal surface by lowering the body and

dragging the anogenital region over it;

this form of marking behavior is particularly

common among arboreal viverrids, which

use it in marking horizontal or nearly

horizontal branches; an example in the Zoo’s

collection is the two-spotted palm civet. The

vontsira or madagascar ring-tailed mongoose

(Galidia elegans) uses this form of marking

behavior either on the ground or ona

horizontal branch.

A number of viverrid species have specialized

scent glands in other parts of the body besides

the anogenital region. In most cases such

glands have evolved from the sebaceous glands

—glands almost universally present in mammals

that produce a greasy secretion used to dress

the fur. In the water mongoose, for instance,

at the base of the vibrissae or whiskers on

the cheeks, there are enlarged sebaceous glands

that produce a substance honey-like in odor;

and these mongooses have been observed

rubbing this secretion on various objects. The

vontsira has a glandular area on the throat,

which also presumably had its origin in the

sebaceous glands; it is used to mark relatively

slender, usually vertical branches.

The fossa has a similar glandular area on the

chest. The gland becomes enlarged only when the

animal reaches sexual maturity, is larger in

the male than in the female, and secretes most

actively in the breeding season. All of this

suggests that its scent plays a role in bringing

the sexes together for mating; but nothing is

known of this species’ breeding habits in the

wild, as indeed little is known of the breeding

habits of any viverrid species in the wild. Almost

all that is known of viverrid breeding biology

comes from observations on captive animals,

and some new data have been collected on a

number of species at the National Zoo.

Recently the Zoo had an apparently successful

mating of binturongs, a species that has rarely

been born and reared in captivity; if the female

is indeed pregnant she will give birth to a

litter of two or three young in mid-May.

Back cover: Banded palm civet (Hemigalus derbyanus).