There were zoos in ancient Babylon, in ancient Egypt, in the Aztec capital of Tenochtitlan, and in ancient China. For example, by 3500 BCE, Hieronkopolis in Egypt had a zoo. Among the animals kept at the zoo were baboons, hippos, elephants. The animals were buried in the city’s elite cemetery. Some of the animals may have been sacrificed on the death of a ruler.
In other words, for thousands of years our species, Homo sapiens, has been capturing and exhibiting other animals. Unlike the ancient zoos, or even the zoos of a century ago, where the animals were kept in cages for human amusement, today’s zoos function as educational institutions. While the animals provide the entertainment which attracts the public, the zoos of today show not only the animals, but their displays help education people about the environment, climate change, endangered species, ecology, and other topics. Shown below are photographs of some of the displays at the Portland, Oregon, Zoo.
Northwest:
One section of the zoo focuses on the Northwest—the area where Portland is located. While animals from this region are featured, the signs and displays along the pathway attempt to explain the local environment and the interrelationships between plants, animals, water, and other aspects of the local ecology.
![photo DSCN1793_zps55fa8828.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1793_zps55fa8828.jpg)
![photo DSCN1812_zpse0918e6f.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1812_zpse0918e6f.jpg)
![photo DSCN1820_zps6ac82223.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1820_zps6ac82223.jpg)
![photo DSCN1822_zps49f4d5ba.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1822_zps49f4d5ba.jpg)
![photo DSCN1833_zpscdbd4919.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1833_zpscdbd4919.jpg)
![photo DSCN1838_zps63634342.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1838_zps63634342.jpg)
![photo DSCN1850_zps911b7296.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1850_zps911b7296.jpg)
![photo DSCN1851_zps2030b3c0.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1851_zps2030b3c0.jpg)
![photo DSCN1853_zps4ecd5872.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1853_zps4ecd5872.jpg)
Condors, such as those shown above, were once common along the Columbia River and as far east as the eastern slope of the Rocky Mountains in Montana (the Blackfoot Indians have a word for condor in their language and have stories about this large bird). The efforts of zoos have resulted in the release of a few breeding pairs back into the wild.
Polar Bears:
![photo DSCN1857_zps8f34d92e.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1857_zps8f34d92e.jpg)
![photo DSCN1860_zps5a5432d8.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1860_zps5a5432d8.jpg)
![photo DSCN1862_zpscfcb8282.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1862_zpscfcb8282.jpg)
![photo DSCN1864_zpse3372e75.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1864_zpse3372e75.jpg)
![photo DSCN1866_zps67b59674.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1866_zps67b59674.jpg)
![photo DSCN1868_zpscc64cb49.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1868_zpscc64cb49.jpg)
![photo DSCN1870_zps34b955b1.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1870_zps34b955b1.jpg)
![photo DSCN1873_zpsc1995870.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1873_zpsc1995870.jpg)
A popular attraction at many zoos is the polar bear exhibit. At the Portland Zoo, the exhibits not only show the bears, but also attempt to educate people about the impact of global warming on these magnificent animals. The exhibits make it clear that: (a) global warming is real, and (b) global warming is the result of human activity.
![photo DSCN1874_zpsac4be18a.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1874_zpsac4be18a.jpg)
![photo DSCN1877_zps7cc9c997.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1877_zps7cc9c997.jpg)
According to the display:
“Climate change is a nature part of Earth’s history.
However, the current rapid climate change is a unique consequence of human activity.
Each year, about 20 billion tons of carbon dioxide (CO2) and other greenhouse gases are released from energy production, cars, and factories.
Only half of the CO2 emissions are absorbed naturally by the biosphere. The remaining CO2 stays in the atmosphere for about 100 years trapping solar heat, which would otherwise radiate back into space. This heat, confined within earth’s atmosphere, increases average global temperatures.”
Malayan Sun Bear:
![photo DSCN1879_zps81ddce16.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1879_zps81ddce16.jpg)
![photo DSCN1882_zps06c38beb.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1882_zps06c38beb.jpg)
![photo DSCN1886_zps1e887104.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1886_zps1e887104.jpg)
![photo DSCN1887_zps180779b4.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1887_zps180779b4.jpg)
![photo DSCN1890_zps341a064a.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1890_zps341a064a.jpg)
![photo DSCN1893_zpsb0fe8d4f.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1893_zpsb0fe8d4f.jpg)
Southeast Asian Pigs:
![photo DSCN1894_zpse8ea4a8c.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1894_zpse8ea4a8c.jpg)
The Visayan Warty Pig is shown above. Native to six islands on the western Philippines, farm expansion and hunting is threatening this species.
![photo DSCN1896_zps769368f0.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1896_zps769368f0.jpg)
![photo DSCN1898_zps75140c7a.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1898_zps75140c7a.jpg)
The Babirusa shown above lives in the moist forests along rivers on several Indonesian islands. Expanding human populations are taking over Babirusa habitat.
Elephants:
![photo DSCN1904_zpsca7e825b.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1904_zpsca7e825b.jpg)
![photo DSCN1906_zps86835978.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1906_zps86835978.jpg)
Orangutan:
![photo DSCN1913_zps6c88f048.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1913_zps6c88f048.jpg)
![photo DSCN1914_zpsb48da51e.jpg](http://i821.photobucket.com/albums/zz139/Ojibwa/Portland%202014/zoo/DSCN1914_zpsb48da51e.jpg)