Universe 25- John Calhoun's NIMH experiment — Transcript

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1. 0:00the work of Dr John Calhoun at the
2. 0:02National Institute of Health in
3. 0:04Washington DC has attempted to answer
4. 0:07this question in a unique experiment
5. 0:10that took years to complete Dr Calhoun
6. 0:13used white mice to study population
7. 0:15growth and its effects on individual
8. 0:20behavior in addition to his renowned
9. 0:23research papers he has recorded some of
10. 0:25these observations on
11. 0:28film in this 16 cell Mouse habitat
12. 0:32utopian conditions of nutrition comfort
13. 0:34and housing were provided for a
14. 0:36potential population of over 3,000
15. 0:40mice yet in spite of ideal conditions
16. 0:44the mouse population met with
17. 0:47catastrophe individuals were kept track
18. 0:49of by color markings on their
19. 0:52fur factors which normally control
20. 0:55population growth such as predation by
21. 0:57owls or cats were eliminated
22. 1:01transmissible disease was also
23. 1:04reduced in effect the mouse Universe
24. 1:07simulated the present situation of a
25. 1:09continually expanding population of
26. 1:15humans to see how Dr Calhoun's Mouse
27. 1:17Universe grew we'll use the familiar
28. 1:20population graph
29. 1:21[Music]
30. 1:23again within the first 100 days the mice
31. 1:26went through the period Dr Calhoun
32. 1:28called strive
33. 1:31this was a period of adjustment
34. 1:33territories were established and nests
35. 1:36were
36. 1:39[Music]
37. 1:40made the next period lasted about 250
38. 1:48days the population of the mice doubled
39. 1:51every 60
40. 1:52days this was called the exploit
41. 1:57period the use of resources became
42. 2:00unequal although each living unit was
43. 2:03identical in structure and
44. 2:05opportunities more food and water was
45. 2:07consumed in some
46. 2:10areas as the population increased most
47. 2:13mice Associated eating and drinking with
48. 2:16the presence of others and crowding
49. 2:18developed in certain
50. 2:22units the third period consisting of 300
51. 2:26days found the population of mice
52. 2:28leveling off this was called the
53. 2:31equilibrium
54. 2:33period Dr Calhoun noticed that the newer
55. 2:36generations of young were inhibited
56. 2:38since most space was already socially
57. 2:45defined at this time some unusual
58. 2:47behavior became
59. 2:50noticeable violence became
60. 2:55prevalent excess males strived for
61. 2:58acceptance
62. 3:01were
63. 3:02rejected and
64. 3:04withdrew huddling together they would
65. 3:06exhibit brief flurries of violence among
66. 3:13themselves the effects of violence
67. 3:16became increasingly
68. 3:22visible certain individuals became
69. 3:25targets of repeated attack these
70. 3:27individuals would have badly chewed and
71. 3:30scarred
72. 3:32Tails other young mice growing into
73. 3:34adulthood exhibited an even different
74. 3:36type of
75. 3:37behavior Dr Calhoun called these
76. 3:40individuals the beautiful
77. 3:42ones their time was devoted solely to
78. 3:45grooming eating and
79. 3:47[Music]
80. 3:49sleeping they never involved themselves
81. 3:51with others engaged in sex nor would
82. 3:54they fight all appeared as a beautiful
83. 3:57exhibit of the species with Keen alert
84. 4:00eyes and a healthy well-kept
85. 4:03body these mice however could not cope
86. 4:05with unusual
87. 4:07stimuli though they looked inquisitive
88. 4:09they were in fact very
89. 4:12stupid Dr Calhoun called the last period
90. 4:15the die phase leading the population
91. 4:18into
92. 4:20Extinction although the mouse Utopia
93. 4:22could house 3,000 the population began
94. 4:25to decline at
95. 4:26[Music]
96. 4:282200
97. 4:31in the shift from the equilibrium to the
98. 4:32die phase each animal became less aware
99. 4:36of Associates despite all animals being
100. 4:39pushed closer together Dr Calhoun
101. 4:41concluded that the mice could not
102. 4:44effectively deal with the repeated
103. 4:45contact of so many
104. 4:49individuals the evidence of violence
105. 4:51increased to the point where most
106. 4:53individuals had had their tails bitten
107. 4:55to some
108. 4:57degree eventually the entire Mouse
109. 5:00population
110. 5:02perished Dr Calhoun's experiment is a
111. 5:05classic example of a typical population
112. 5:08and its growth when left
113. 5:11unchecked research in this area
114. 5:13continues under his supervision
115. 5:15currently Dr James Hill has taken the
116. 5:18basics of the calhon experiment to study
117. 5:21social behavior even more closely in his
118. 5:25experiment rats are used instead of mice
119. 5:28healthy individual tool are selected to
120. 5:30start the
121. 5:32population the rats are anesthetized so
122. 5:35that Dr Hill can perform a minor
123. 5:37operation necessary to the success of
124. 5:40his
125. 5:41experiments a small electromagnetic
126. 5:44encapsulated device is implanted into
127. 5:47every
128. 5:48rat this small unit enables sensing
129. 5:51devices to keep track of the movement
130. 5:53and position of each individual in the
131. 5:58population
132. 6:01after surgery the rats are introduced to
133. 6:04their new multi-leveled home all at the
134. 6:06same
135. 6:12time the rats immediately begin to
136. 6:14explore their new environment prior to
137. 6:17organizing territories and
138. 6:19nesting Dr Hill will Trace how
139. 6:22individuals move about in crowded
140. 6:25situations this movement is followed by
141. 6:27tubular sensing devices
142. 6:30every time a rat enters or passes
143. 6:32through a tube the unit detects and
144. 6:35registers its presence this constant
145. 6:38movement is monitored by
146. 6:41computer nesting activity is also
147. 6:45studied Dr Hill has observed that the
148. 6:48larger the population the less care a
149. 6:51mother gives to her nest and
150. 6:54young the same type of individuals that
151. 6:56resulted in the mouse Utopia are also
152. 6:59Emer emerging in the rat
153. 7:01population there are aggressives
154. 7:04asocials and
155. 7:06outcasts though these studies use
156. 7:08animals the findings about population
157. 7:11growth and individual Behavior are being
158. 7:13closely compared to our own human
159. 7:17population like all populations that
160. 7:19have existed on this planet many
161. 7:22researchers believe that the human race
162. 7:24has reached a crucial point in the
163. 7:26exploit phase a point where important
164. 7:28decision must be made and careful
165. 7:31planning implemented if we are to
166. 7:36survive the study of plant and animal
167. 7:39populations helps us to make decisions
168. 7:42about the future of our human population
169. 7:45so that we may maintain our own balance
170. 7:49with
171. 7:49[Music]
172. 7:58nature
173. 8:04[Music]
174. 8:14[Music]
175. 8:21a