Evolution by natural selection.
survival of the fittest=natural selection
Curare will bind to the receptor but it doesn't cause the ion to flow inside. This will prevent the person from sent signal to the muscle. When the person trying to move the muscle, curare will also prevent acetylcholine to bind so there will be no muscle contractions. The symptoms would be paralyzed of muscle that uses ach receptor.
Adaptation is a phenomenon that is about adjusting certain features to environmental conditions. Ie. birds are adapted to flight as they possess wings, very efficient lungs etc. or tropical plants are adapted to high temperature and humidity as they modified their photosynthesis process. but if some creature is adapted to the specific habitat or conditions, it is hard for it to manage in another habitat/different conditions. ie. birds are fast in the air but on the ground they are quite weak and prone to predators' attacks.
Answer:
1.lunar 2.solar 3.earth 4.the moon 5.sun