### extremely broad discipline | anthropology:

Physical anthropology
* examines human genetics, growth and development and biological evolution.
* explains the physical nature and development of humankind.
* focuses on the biological aspects of the human species.
* includes the study of linguistic variation as it relates to climate
  - training in gross anatomy, osteology, forensics, and fertility
* is anthropology
  - both a biological science and a social science
  - one of the two main divisions of anthropology
* is the study of human biology and evolution
  - remains from archaeological sites
  - humans as biological organisms
* large, and dynamic field.
* looks at human origins and evolution.
* maps human biological evolution and physiological adaptations.
* studies the evolution of the human biological form.

Sociocultural anthropology
* emphasizes in-depth field research.
* investigates customs and products of civilization.
* provides a framework for the study of human social and cultural activity.

Urban anthropology
* Much urban anthropology is oriented around exploring and explaining social problems.
* is the study of human beings and their cultural institutions in cities.

### extremely clean animals:

Ringtail cat
* Most ringtail cats have claws.
* Some ringtail cats have rings.
* are extremely clean animals.

Extremely dangerous polonium
* Polonium also forms a hexafluoride, but it is understudied
  - decay product of radon, which in turn decay product of uranium
* Polonium has a few commercial uses
  - more isotopes than any other element, all of which are radioactive
  - no biological role
  - is also combined with beryllium to form neutron sources
* Polonium is an extremely dangerous material
  - substance
  - rare natural element
  - both toxic and radioactive
  - chemical elements
  - distributed in soft tissues as well as bone
  - highly unstable, radioactive and toxic
  - hundreds of times more radioactive than uranium
  - metal
  - metallic elements
  - produced in nature when other radioactive elements break down
* Polonium is radioactive and excessivley rare in nature
  - substances
  - removed from surface waters by the rain of faeces descending from zooplankton
* Polonium is used as a neutron source in nuclear reactors and as an alpha-particle generator
  - in special anti-static brushes
  - radioactive element produced by the decay of uranium
  - radioactive, extremely rare semi-metal
  - readily reacts with dilute acids, but only slightly with alkalis
  - relatively rare element
  - usually is isolated from by-products of the extraction of radium from uranium minerals. * is highly unstable, radioactive and toxic. This makes it difficult to handle, and potentially dangerous, even in very small amounts. One gram of Po will self-heat to a temperature of around. It also vaporizes easily
* Polonium very rare element in nature
+ Group 16 element: Chemical elements :: Periodic table
  * Group 16' is the third last group in the periodic table. This group is called the 'oxygen family' or the 'chalcogens'. The elements in this group are oxygen, sulfur, selenium, tellurium and polonium. The first three elements are nonmetals and the last two are semimetals. Polonium is radioactive. Oxygen is a colorless gas.