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This list excludes tools and tool use attributed to non-hominin species. See Tool use by non-humans . Since there are far too many hominin tool sites to list on a single page, this page attempts to list the 6 or fewer top candidates for oldest tool site within each significant geographic area.
A Petri dish (alternatively known as a Petri plate or cell-culture dish) is a shallow transparent lidded dish that biologists use to hold growth medium in which cells can be cultured, [1] [2] originally, cells of bacteria, fungi and small mosses. [3] The container is named after its inventor, German bacteriologist Julius Richard Petri.
Individual cells contain and secrete a variety of small peptides, made up of between four and 20 amino acids, which are detected by neighbouring cells. Each peptide can be used individually to send a signal to other cells, but also sequentially or together in different combinations, creating a huge number a different types of signals.
Stone tool use – early human (hominid) use of stone tool technology, such as the hand axe, was similar to that of primates, which is found to be limited to the intelligence levels of modern children aged 3 to 5 years. Ancestors of homo sapiens (modern man) used stone tools as follows: Homo habilis ("handy man") – first "homo" species.
4000 BC – First use of light wooden ploughs in Mesopotamia (Modern day Iraq) 3500 BC – Irrigation was being used in Mesopotamia (Modern day Iraq) 3500 BC – First agriculture in the Americas, around Central Amazonia or Ecuador; 3000 BC – Turmeric, cardamom, pepper and mustard are harvested in the Indus Valley civilisation.
After collection, the grass was used as material to create matting and bedding. [6] The sickle in general provided the convenience of cutting the grass as well as gathering in one step. In modern times, the sickle is being used in South America as tool to harvest rice. Rice clusters are harvested using the instrument and left to dry in the sun.
The pseudopods are used for locomotion, anchoring, excretion, test construction and in capturing food, which consists of small organisms such as diatoms or bacteria. [ 35 ] [ 33 ] Aside from the tests, foraminiferal cells are supported by a cytoskeleton of microtubules, which are loosely arranged without the structure seen in other amoeboids.
While many plants have been used for food, a small number of staple crops including wheat, rice, and maize provide most of the food in the world today. In turn, animals provide much of the meat eaten by the human population, whether farmed or hunted, and until the arrival of mechanised transport, terrestrial mammals provided a large part of the ...