Social Behaviour

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Across:

1. Unselfish behaviour whereby an animal will help another at its own expense. (8)
4. Position in a hierarchy. (4)
6. An animal prepared to give. (5)
7. Type of behaviour which is unthreatening. (11)
8. Working together. (11)
9. Relationship which is very close and benefits all animals. (8)
10. Animal at the top of the pecking order. (8)
12. Species which plays an important role in the structure of an ecosystem. (8)
13. Process which favours and helps close relatives. (3,9)
14. System where the members are ranked. (6,9)
15. Linear form of social organisation. (7,5)

Down:

1. Type of altruism when a parent sacrifices itself to ensure its offspring survive. (8)
2. Organism which protects the group by the males forming a barrier round the calves and females. (4,2)
3. Animal lower down the rankings. (11)
5. Collection of animals similar to each other. (9,5)
11. Animal which gains from altruism. (9)