1 The posterior pituitary lobe releases two hormones that are produced in the hypothalamus:  Oxytocin, which is responsible for stimulation of milk ejection (milk letdown) and for stimulation of uterine smooth muscle contraction at birth.
Crayfish and crawfish are crustaceans living in freshwater with a great resemblance of the lobsters. However, their size is smaller compared to the lobsters.
They are colloquially called crawfish or crawdads. Most species of crayfish live in freshwater. All of them play a significant role in the environment, keeping it clean and serving as a food source for birds and other aquatic animals.rayfish are small aquatic creatures, approximately one to six inches in length. They take on a muddy green, yellow or red colorâsometimes even black. There are 540 species of crayfish worldwideâabout 400 of these are found in North America.