Ecotourism also has an effect on species through the value placed on them. "Certain species have gone from being little known or valued by local people to being highly valued commodities. The commodification of plants may erase their social value and lead to overproduction within protected areas. Local people and their images can also be turned into commodities". Kamuaro points out the relatively obvious contradiction that any commercial venture into unspoiled, pristine land inevitably means a higher pressure on the environment. The people who live in the areas now becoming ecotourism spots have very different lifestyles than those who come to visit. Ecotourism has created many debates based on if the economic benefits are worth the possible environmental sacrifices. Who benefits? Most forms of ecotourism are owned by foreign investors and corporations that provide few benefits to the local people. An overwhelming majority of profits are put into the pockets of investors instead of reinvestment into the local economy or environmental protection leading to further environmental degradation. The limited numbers of local people who are employed in the economy enter at its lowest level and are unable to live in tourist areas because of meager wages and a two-market system.In some cases, the resentment by local people results in environmental degradation. As a highly publicized case, the Maasai nomads in Kenya killed wildlife in national parks but are now helping the national park to save the wildlife to show aversion to unfair compensation terms and displacement from traditional lands.
Upright MRI was more than twice as sensitive as standard MRI, likely because gravity affects cerebellar position.Cases of congenital Chiari malformation may be explained by evolutionary and genetic factors. Typically, an infants brain weighs around 400g at birth and triples to 1100-1400g by age 11. At the same time the cranium triples in volume from 500 cm3 to 1500 cm3 to accommodate the growing brain. During human evolution, the skull underwent numerous changes to accommodate the growing brain. The evolutionary changes included increased size and shape of the skull, decreased basal angle and basicranial length. These modifications resulted in significant reduction of the size of the posterior fossa in modern humans. In normal adults, the posterior fossa comprises 27% of the total intracranial space, while in adults with Chiari Type I, it is only 21%. H. neanderthalensis had platycephalic (flattened) skulls. Some cases of Chiari are associated with platybasia (flattening of the skull base). History
The history of Chiari malformation is described below and categorized by the year:

1883: Cleland was the first to describe Chiari II or Arnold–Chiari malformation on his report of a child with spina bifida, hydrocephalus, and anatomical alterations of the cerebellum and brainstem. 1891: Hans Chiari, a Viennese pathologist, described the case of a 17-year-old female with elongation of the tonsils into cone shaped projections which accompany the medulla and are crammed into the spinal canal.