March 29, 2009
This past Sunday, I went to the Smithsonian National Museum of Natural History in Washington, DC. At the museum, there are various exhibits displaying the wonders of the Earth, such as the Oceans hall, and a Forensic archaeology exhibit. This museum lends a new definition to the term "art:" it is not just manmade anymore, it is also nature created.
The Sant Ocean Hall
Interactions of humans and the ocean:
The ocean has a tremendous overarching impact on human life. The ocean is responsible for the hydrologic cycle: 97.2% of the water for this cycle comes from the ocean. The ocean is a major contributor to Earth's atmospheric oxygen. The ocean supplies the Earth with at least half of its' oxygen and is equal to the amount of oxygen produced from the green land plants. The ocean also absorbs carbon dioxide, which is a green house gas. This action regulates the Earth's temperature and ensures that the Earth will not get too hot because of excess carbon dioxide. This display was portrayed on posters along one of the parameters of the hall. It was mostly factual displaying only a few images.
Adaptations of modern marine life:
Marine life has evolved over the years to adapt to different habitats and life styles. The exhibit displayed this through the use of fossils, posters, photographs, and preserved specimen. Whales were originally mammals that had moved to the water in search of a better food source. Because of this move, whales lost their teeth and developed baleen, net-like plates hanging from the upper jaw, instead. The baleen was more beneficial to the whales in the water because the whales were now able to strain small prey, like phytoplankton, from the water. Baleen had in effect made it easier for the whales to eat. The Baleen whale display was centered around the theme of the evolution of how these whales feed. Another display pertaining to the adaptations of marine life was centered around the organisms' environment. Because there is very little light in the Twilight Zone, the marine life evolved specialized eyes to be able to see in dark waters. The also evolved the ability to produced light through bioluminescence. These organisms use bioluminescence to attract mates and to lure or avoid predators. Also, since food is rare and competition is scarce in this habitat, the fish evolved saw like teeth and larger mouths in order to get a quick mouthful of meat.
Written in Bone: Forensic Files of the 17th Century Chesapeake
Bones tell a story. Forensic anthropology gives hard evidence of populations that are no longer in existence. Skull shape tells a lot about a person. Through it's structure, forensic anthropologists were able to determine the race of the body. For example, a Native American skull has a wider face and a broader cranial vault. When exhuming the bones of this settlement, the forensic anthropologists were able to deduce the demographics of the population through looking at the different physical features of the skull. In this particular settlement, the anthropologists found evidence of Europeans, Native Americans, and Sub Saharan Africans. This display was portrayed through the juxtaposition of the skulls of the above mentioned races. Bones can also tell the age of the body, and hence the health of the population. For example, if most of the people had lived to an old age then that population was probably healthy. There are several different ways in which anthropologists can assign an age to a body. The pelvis is a useful indicator since it changes over time. With the pelvis, anthropologists can predict the age of a person up to the age of 55 with a 5 year error. The cranium can also be used to predict age. During childhood, the bones that enclose the brain start to knit together, but during adulthood these lines gradually are erased. This display had a picture of half an old man and a picture of half a boy lined up to make one person. Superimposed over this picture were the parts of the body that displayed age relative to their location in the picture of the person.
Orchids Through Darwin's Eyes
Orchids are an excellent display of evolution because there are so many different variations of the species. Darwin, himself, studied orchids. The Angraecinae group has a long hollow spur that contains nectar that only a moth with a Proboscis, a long straw like tongue, can gather. This flower usually blooms on a long spike that sways in the breeze. It is pale in color in order to attract night flying moths. However, the real attraction to the insects is the fragrance that the flower emits. This species of flower portrays the symbiotic relationship of species: if the moth were to become extinct then the flower would lose it's source of pollination and it too would become extinct. Dr. Rod Peakall examined the Ophrys species. These flowers would attract pollinators by mimicking the female insect in form, smell, and color. These flowers then bloom when the male insects start to mate but before the females appear. The male then pollinates the flower by trying to mate with it. These flowers do not reward the insects for their troubles. However, the insect continues to mate with the flower because competition to mate is fierce, therefore, the male does not care who it mates with as long as it mates. This species of flowers depicts the evolution of a symbiotic relationship in which the flower evolved to look like an insect in order to maximize it's pollination. The information from this display was shown to the public on three part plackets in front of various groups of flowers. One part of the placket would give general evolutionary information about the flower, the second part would give a diagram of the flower, and the the third part had a quote from the scientist who examined it.
The Janet Annenberg Hooker Hall of Geology, Gems, and Minerals
In this exhibit, there is a display of a huge sheet of copper. It was created by North America when it started to split into two. During this splitting, large amounts of molten rock rose from the Earth's depth and solidified. Hot water then dissolved the copper from the rocks. The copper then seeped into the overlying layers of shale, which caused the copper to be deposited into sheets. Alongside the metal was a map indicating that the copper had come from Michigan. In another part of the exhibit was an enormous quartz crystal in which several crystals had grown together to form the giant crystal portrayed. Each of the individual crystals had a six sided pencil shape to it, which is typical of quartz. There was a map next to the crystal that showed that it was discovered in Africa. This particular quartz was found in a big cave, which allowed for the quartz to grow in size. A quartz crystal forms when silicon and oxygen move around in hot water in the Earth's crust. As the atoms join together, a crystal begins to form. The outer shape of the crystal reflects the symmetrical arrangement of the atoms.
The recent economy does not look too bright. Because of this, funding for various institutions, including museums are being cut back. However, museums still have to remain cost effective, informative, and user friendly. To achieve this, museums could start to switch to using more technological exhibits. Technological exhibits are easier to maintain, and thus cheaper, and are more interactive.
Plants had their own Big Bang when they rapidly diversified 130 million years ago. This baffled many scientists as to why plants would diversify over only a short span of five million years. Through genetic analysis, scientists were able to infer that three lineages of plants were able to evolve in a brief amount of time. Although scientists know that diversification happened rapidly, they are still baffled as to the cause of it. New ideas are being looked at, such as the possibility of climate change, or the development of a new evolutionary trait.
Bryner, J. 26 November, 2007. "Evolutionary 'Big Bang' Created Florist's Paradise". LiveScience. 5 April 2009.
When colonialists moved to Chesapeake Bay, one of the many adaptations that they encountered was a change in diet. The diet of these colonials was studied through the use of isotopes in the bones. The bones of males, females, and children would be compared against each other. Skeletal analysis of this community indicated a high mortality rate and extreme physical activity. Some bodies were exhumed from a cemetery that was believed to have been creating during 1609-1610 when food was scarce. These bodies were compared to bodies that were exhumed from a cemetery created at a later date. There was a variation between the bodies from the two cemeteries, which meant that their diets varied. However, this study is inconclusive as to exactly what they ate because it would be impossible to estimate the contributions of the various food sources to the diet such as marine food and wild food. This study was only done on a small sample, and more research is being done on this topic as more bodies are being exhumed.
Ubelaker, D., D.W, Owsley. 2003. Isotopic Evidence for Diet in the Seventeenth-Century Colonial Chesapeake. American Antiquity 68: 129-139.