ddoyleperkin's blog

Herring gulls and Black-backed gulls are two separate species of seagull that live side by side, exhibiting a wide variety of identical behaviors that allow them to communicate during significant times in their lives. These gulls breed in close quarters on coastal islands in the North Atlantic. Because of the proximity to one another, these seagulls have had to develop intricate ways of communicating with one another in order to successfully court mates, breed, nurture young, and survive. It is important to understand that animals send signals with the understanding that they will receive a response. There are three main categories of gull signaling behaviors: territoriality/aggression, parental care, and courtship. When it is a question of territoriality, gulls will always prefer to signal before engaging in aggression. One such signal is known as upright posture, which is an extension of the gull’s back and the slight spread of its wings. Upright posture is a threat display used by gulls to maintain or negotiate territory in their close-knit colonies. This display is used most often right after chicks hatch, in an effort to solidify their territory to protect their young. However, before chicks can hatch, gulls must court mates. To begin courtship, females will fly around the colony and assess the fitness of males from the air. When they find a suitable male, they will land in his territory and immediately assume one very important behavior: begging. The begging behavior is learned as a chick to ask their parents for food, but females use it during courtship to gain the trust of the unfamiliar male. This behavior is characterized by an outstretching of the neck upwards, directly into the face of the male. During this time, the female is literally asking the male for food. If the male complies and gives the female food, their pairing begins. Once gulls are paired, they establish their territory, establish a nest, and begin copulation. Copulation begins by using the same behavior that the chicks and the female once used; the begging behavior. The female gull will exhibit this begging behavior until the male agrees to copulate. The male will then stand on the back of the female and begin mating. The mating ritual is an interesting one because the male gull will use a behavior only seen during this time. Once mating has begun, the male will elicit what is known as a mating call; a unique sound that can only be heard during the mating season. The upright posture, begging, and mating call are among many important behaviors that these gulls must use to communicate, care for their young, and stay alive.

Hormones are molecular messengers that carry out their action via hormone receptors. Hormone receptors are proteins that receive hormones secreted from various glands throughout the endocrine system. These receptors are connected to one or more effector networks that allow them to mediate the action of the hormone received. If a hormone receptor is present in a certain tissue, it outlines the target cells of a specific hormone as well as allowing for a mechanism by which the hormone can act. These receptors are known to elicit widespread effects on the human body through the use of something called “second messengers”. A second messenger relays information from the receptor to different effector systems associated with that receptor, for example, the arrival of a hormone. A very important second messenger in the endocrine system is cyclic adenosine monophosphate or cAMP. This molecule allows the endocrine system to mediate the effects of many different hormones in many different tissues. Hormone receptors are the link between the desired effect of a hormone signal and the actual effect of hormone action.

What appeared in my container was a seemingly simple, elongate insect in an early stage of its life cycle, perhaps its larval state. This organism was beige in color with a dark brown coloration at its head. This insect consisted of a head with a mouth and no eyes, a 3-4 cm long body separated into about 12 segments with 6 legs very proximal to its head, and a caudal end with what looked like two separate appendages sticking out at the end. This organism moves by first feeling its immediate surroundings with its true legs, then contracting, sending a wave from the caudal end of its body to the rostral end, grabbing the ground with pro-legs found near the middle and back of the ventral side of its body. Other notable visual characteristics include the dark coloration of the legs and the tiny dark spots that are present on either side of each segment of its body. There are no notable smells or sounds coming from the organism.

The way that the insect moves seems to be random. It grasps at surfaces, looking for obstacles until it decides to move forward. After shining a flashlight on it, I discovered an adverse reaction, so the organism prefers to be in the dark. It also has a hard time returning its legs to the ground once it has been flipped over.

What appeared in my container was a seemingly simple, elongate insect in an early stage of its life cycle, perhaps its larval state. This organism was beige in color with a dark brown coloration at its head. This insect consisted of a head with a mouth and no eyes, a 3-4 cm long body separated into about 12 segments with 6 legs very proximal to its head, and a caudal end with what looked like two separate appendages sticking out at the end. This organism moves by first feeling its immediate surroundings with its true legs, then contracting, sending a wave from the caudal end of its body to the rostral end, grabbing the ground with pro-legs found near the middle and back of the ventral side of its body. Other notable visual characteristics include the dark coloration of the legs and the tiny dark spots that are present on either side of each segment of its body. There are no notable smells or sounds coming from the organism.