Biology - Pan

Question 1

What family do Pan belong to?

Answer 1

Hominidae, one of three members of the great apes

Question 2

What is the diet of chimpanzees?

Answer 2

Primarily vegetarian

Question 3

Describe the physical appearance of chimpanzees.

Answer 3

Tailless, arms longer than legs, protrusive lips, prominent ears, and a short, opposable thumb. Short foot with long, strong big toe.

Question 4

Variation in what results in white hair tuffs on the chin and anal region?

Answer 4

Age and sex

Question 5

What is the dental formula of Pan? Describe canines.

Answer 5

2 (I2/2, C 1/1, P 2/2, M 3/3) for 32 total teeth. Well-developed canines.

Question 6

Describe the stomach and cecum of Pan.

Answer 6

Simple stomach, cecum has an appendix like humans.

Question 7

What structure do Pan have in the neck and axillary space?

Answer 7

Extensive laryngeal (air) sacs

Question 8

How do chimpanzees move?

Answer 8

Primarily a quadrupedal walk, interspersed with short distances of brachiating and standing upright to increase visual range.

Question 9

Where do chimpanzees spend most of their time? Where do they sleep?

Answer 9

Arboreal 50-75% of the time. Sleep in tree nests newly built each night, seldom less than 15 feet above ground.

Question 10

What is unique about the chimpanzees size in biomedical research?

Answer 10

Traditionally the largest NHP model in biomedical research.

Question 11

What historical contributions did chimps make to vaccine research?

Answer 11

Vaccines for hepatitis A and B, advance understanding of hepatitis C. Adenoviruses isolated from chimps shown promise as vectors for Ebola and malaria vaccines.

Question 12

Why were chimps used in hepatitis C research?

Answer 12

Only animal model that closely recapitulates hepatitis C virus infection and pathogenesis.

Question 13

What occurred in 1995 regarding chimps?

Answer 13

NIH instituted a moratorium on breeding NIH-owned or supported chimps as there were enough chimps to meet research needs without breeding.

Question 14

What occurred regarding chimp research in December 2010? What was the decision made?

Answer 14

NIH commissioned a study by the Institute of Medicine (IOM) to assess need for chimps in biomedical/behavioral research. Report published in December 2011 recommended stringent limits on use with a set of principles and criteria to be met when deciding to conduct research with chimps. NIH accepted IOM report, charged NIH Council of Councils Working Group on implementation of these recommendations and to provide recommendations on size and placement of NIH-owned chimps.

Question 15

How many chimps were retired from research? What will this result in?

Answer 15

All but 50 NIH-owned chimps. Ultimately will result in a geriatric chimp population. Predicted by 2037, federally funded captive chimp population will cease to exist.

Question 16

How has the US Fish and Wildlife Service proposed to classify chimps? When did this occur?

Answer 16

As endangered, like wild populations, instead of threatened, even though they bred well in captivity. 2013

Question 17

What are the species of chimpanzees? How many subspecies exist? How have each contributed to research?

Answer 17

Pan troglodytes - common chimpanzee. Most use in research.
Pan paniscus - bonobo, dwarf chimp, pygmant . Limited use, primarily in behavior and cognition.
Four subspecies of Pan troglodytes

Question 18

What is the diploid chromosome number of chimps? What are their blood types?

Answer 18

48 (compared to 46 in humans). Similar blood types to the ABO system, must be crossmatched before transfusions.

Question 19

Describe location and population numbers of chimps in the wild?

Answer 19

Across equatorial Africa. Forested areas from Sierra Leone and Guinea eastward to the River Niger. Numbers continue to decline. Fewer than 200,000 in wild.

Question 20

Where are NIH-supported chimps currently housed? What other locations house chimps?

Answer 20

Three facilities: Alamogordo Primate Facility operated by Charles River, Michale E. Keeling Center for Comparative Medicine and Research at University of Texas MD Anderson Cancer Center, Texas Biomedical Research Institute in San Antonio, Texas
Non-NIH: Yerkes National Primate Research Center at Emory, New Iberia Research Center at the University of Louisiana-Lafayette

Question 21

What environments do chimps live in?

Answer 21

Savannah, rainforests, montane and swamp forests, dry woodlands

Question 22

What is the lifespan of a chimp in the wild and captivity?

Answer 22

Wild: 15-19 years
Captivity: 40-50 years

Question 23

Are chimpanzees sexually dimorphic? How?

Answer 23

Yes, males weight 40-60 kg, females weigh 32-74 kg.

Question 24

Describe the social structure of chimpanzees.

Answer 24

Male-dominated fission-fusion groups that favor male philopatry. Females emigrate from natal communities 1-2 years after puberty.

Question 25

Do chimps use tools?

Answer 25

Yes, first documented in 1960 by Jane Goodall

Question 26

How is the onset of puberty detected in female chimpanzees? How does this relate to the onset of menarche? How does this differ in captivity?

Answer 26

Onset of cyclic swelling of anogenital tissue. May occur 1-1.5 years before menarche, usually seen between 8 and 11 years of age. Sexual maturity in captivity can occur 2-3 years earlier due to enhanced nutrition.

Question 27

Are chimps seasonal breeders?

Answer 27

Not strict seasonal breeders, but geographically associated seasonal peaks in sexual receptivity have been observed.

Question 28

Describe the menstrual cycle of chimps.

Answer 28

37 day menstrual cycle. Estrus coincides with a 5-6 day period of max swelling of the anogenital tissue. Ovulation occurs 1-6 days before detumescence.

Question 29

How long is the chimp gestation period? How can pregnancy be determined?

Answer 29

7.5-8 month gestation period (227-235 days). Human pregnancy kits are dependable, as is amenorrhea and change in sex-cycle swelling.

Question 30

How many offspring does a chimp typically birth? How long does labor take? Is dystocia common?

Answer 30

Singletons, twinning rat comparable to that in humans. Onset of labor is rapid, parturition usually takes 30 minutes. Dystocia rare as infant birth weight is low relative to weight and pelvic dimensions of female.

Question 31

When is the placenta passed? What occurs with it?

Answer 31

Passed within an hour of delivery, placentophagia not uncommon.

Question 32

When do chimps achieve the highest reproductive rate? When does menopause occur, and what is this associated with?

Answer 32

Highest reproductive rate between 15-30 years. Chimps reach follicular exhaustion and corresponding menopause around 50 years of age.

Question 33

When do male chimps reach puberty? How is this altered in captivity? Do most sexually mature males successfully breed?

Answer 33

7 years. In captivity, viable sperm production and implantation can occur earlier based on male’s exposure to/experience with sexually mature females. When social housed, most males develop successful breeding skills, but personalities, social histories, and experience will influence.