The International Union for the Conservation of Nature (IUCN) lists 9 species of spider monkey, which can be found in rain forests from southern Mexico through Brazil. The IUCN lists 3 spider-monkey species as Critically Endangered; 5 species of spider monkey are listed as Endangered, and 1 species is Vulnerable.
The foundations of the endocrine system are hormones and glands. A gland is a group of cells that produces and secretes hormones. Hormones are the body's chemical messengers. They send and relay messages between different systems. Many different hormones move through the bloodstream.
The nervous system and the circulatory system work together in that  the brain sends signals to the heart that cause it to pump. The  circulatory system works with the excre â¦ tory system because waste  materials are transported by blood to the organs of the excretory  system. The nervous system works in your body by sending signals to other body systems for example the brain sends a signal to the circulatory system that tells the heart to pum â¦ p blood. 36 people found this useful.