Isis (Ancient Greek: Ἶσις, original Egyptian pronunciation more likely Aset) is a goddess in Ancient Egyptian religious beliefs, whose worship spread throughout the Greco-Roman world. She was worshipped as the ideal mother and wife as well as the patron of nature and magic. She was the friend of slaves, sinners, artisans, and the downtrodden, and she listened to the prayers of the wealthy, maidens, aristocrats, and rulers. Isis is often depicted as the mother of Horus, the hawk-headed god of war and protection (although in some traditions Horus's mother was Hathor), and she is depicted suckling him in an attitude similar to that of the Virgin Mary with the Child Jesus. Isis is also known as protector of the dead and goddess of children.

The name Isis means "Throne". Her headdress is a throne. As the personification of the throne, she was an important representation of the pharaoh's power. The pharaoh was depicted as her child, who sat on the throne she provided. Her cult was popular throughout Egypt, but the most important sanctuaries were at Behbeit El-Hagar in the Nile delta, and, beginning in the reign with Nectanebo I (380–362 BCE), on the island of Philae in Upper Egypt.

Swarm behaviour, or swarming, is a collective behaviour exhibited by animals of similar size which aggregate together, perhaps milling about the same spot or perhaps moving en masse or migrating in some direction. As a term, swarming is applied particularly to insects, but can also be applied to any other animal that exhibits swarm behaviour. The term flocking is usually used to refer specifically to swarm behaviour in birds, herding to refer to swarm behaviour in quadrupeds, shoaling or schooling to refer to swarm behaviour in fish. Phytoplankton also gather in huge swarms called blooms, although these organisms are algae and are not self propelled the way animals are. By extension, the term swarm is applied also to inanimate entities which exhibit parallel behaviours, as in a robot swarm, an earthquake swarm, or a swarm of stars.

From a more abstract point of view, swarm behaviour is the collective motion of a large number of self-propelled entities. From the perspective of the mathematical modeller, it is an emergent behaviour arising from simple rules that are followed by individuals and does not involve any central coordination.

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