Segment 10 Illustrative Examples Part 2

3.D.1 Cell communication processes share common features that reflect a shared evolutionary history c. In single-celled organisms, signal transduction pathways influence how the cell responds to its environment. Illustrative example: • Use of chemical messengers by microbes to communicate with other nearby cells and to regulate specific pathways in response to population density (quorum sensing) • Use of pheromones to trigger reproduction and developmental pathways (826-828) • Response to external signals by bacteria that influences cell movement.

3.E.1 Individuals can act on information and communicate it to others a. Organisms exchange information with each other in response to internal changes and external cues, which can change behavior. Illustrative example: • Fight or flight response • Predator warningsna • Protection of young (830) • Plant-plant interactions due to herbivory • Avoidance responses (824) b. Communication occurs through various mechanisms. Evidence of student learning: 1. Living systems have a variety of signal behaviors or cues that produce changes in the behavior of other organisms and can result in differential reproductive success. • Herbivory responses • Territorial marking in animals (830) • Coloration in flowers 2. Animals use visual, audible, tactile, electrical and chemical signals to indicate dominance, find food, establish territory and ensure reproductive success. • Bee dances (829-830) • Bird songs (828) • Territorial marking in mammals (830) • Pack behavior in animals (833) • Herd, flock, and schooling behavior in animals (834) • Predator warning (828) • Colony and swarming behavior in insects (833) • Coloration (863-864)  

Bee Dances The round dance indicates that the bee has located a profitable food source close to the hive. It is used for food sources 25-100 meters away from the hive or closer. Through the round dance, the scout bee communicates information pertaining to the distance and direction the food source is from the hive to the follower bees. During the round dance bees distribute some of the new-found nectar to follower bees. Then the scout bee will begin running in a small circle, switching direction every so often. After the dance ends, food is distributed to the comb and the dance may be repeated three or more times. When the food source is relatively far away (over 50 meters), the round dance transitions into the waggle dance. An important factor to the waggle dance is the angle on the honeycomb, which relates to the direction from the hive and sun that the bees should fly. The waggle dance includes information about the direction and energy required to fly to the goal. Energy expenditure (or distance) is indicated by the length of time it takes to make one circuit. For example a bee may dance 8-9 circuits in 15 seconds for a food source 200 meters away, 4-5 for a food source 1000 meters away, and 3 circuits in 15 seconds for a food source 2000 meters away. Natural selection is expected to favor efficient foraging patterns and this creates the basis of a large body of optimal foraging theory.

Bird Songs Birds songs are a type of auditory communication that have many different purposes. They are usually more effective than a visual or chemical communication. Some purposes of bird songs include distress, courting, and marking territories. It is typically male birds that do the “singing”.

COLONY AND SWARMING BEHAVIOR IN INSECTS LIVING IN A COLONY Benefits, but also negatives ADVANTAGES Greater reproductive benefit compared to its cost The insects join together when faced with a predator (increasing survival) Proximity allow for quick and successful reproduction to ensure the population does not die Multiple bodies allow for insects to forage for food quicker and more efficiently DISADVANTAGES Crowded, competition arises Dominant nature comes out in some species Females are viewed as subordinate to their male counterparts This close proximity can allow diseases to spread easily

SWARMING SWARM INTELLIGENCE Insects are led by a collective mind instead of following individual wishes Explains why ants can construct into mechanisms of survival when pressured While individual ants are unable to survive Reasoning: To collect food for the colony A swarm of insects will be able to locate the most efficient way to reach their food Can make quick and decisive decisions with the assist of many helping hands Can also be a time for mating (mating swarming)

Response to Change Organisms must be able to respond to change in their environment to survive Chemotaxis is movement of something in response to a chemical stimulus, such as a macrophage is guided towards a site of infection or injury Chemokinesis is movement of something in response to a chemical stimulus, however, it is without a direction; such as certain flagella movements 

Timing is regulated by multiple mechanisms Internal and external signals commences specific physiological events Migration often occurs when a supply of food is scarce The reproductive system for most animals is the latest to develop, thus ensuring proper time before an organism is capable to reproduce Many species of animals use hibernation during the winter to conserve energy while sufficient food is not available 

Timing of behavior are regulated by multiple mechanisms and are important in natural selection Timing of behavior is vital to natural selection Hibernation allowed for some species of animals to have a much higher survival rate during the winter due to less energy expenditure Migration allows for the animals to take over a new environment and which can create new problems for the new ecosystem which they inhabit

Individuals react and communicate Most animals use body language as well as sound and smell to communicate with each other Bees dance when they find nectar for communication purposes Kangaroos thump their hind legs to warn others of danger Whales breach to send messages to other whales

Coloration Yellow jacket Mimicry – occurs when one species resembles another that possesses an overt antipredator defense. A mimic that lacks the defense of the organism is called a Batesian mimic Ex: a flower fly has the same appearance as a yellow jacket but is incapable of stinging A mimic that shares the same protective defense is called a Müllerian mimic Ex: the bumblebee and the yellow jacket have the same appearance, and both use stinging as a defense Batesian mimic Müllerian mimic Flower fly Bumblebee

Coloration cont. B. A. C. A. camouflage B. warning coloration C. startle response Camouflage – the ability to blend into the background. Ex: lizards can blend into the bark of trees Warning coloration – tells the predator that the prey is potentially dangerous Ex: poison arrow frogs are brightly colored to warn predator that they are dangerous o touch Startle response – a largely unconscious defensive response to sudden or threatening stimuli Ex: the large false head of the South American lantern fly may startle a potential predator A. C.