Question

homework due: thursday, september 18 for questions 1-3 identify the types of symbiotic relationships described in the following scenarios. justify each answer with a piece of evidence from the text. 1. *within a dense forest, two species of trees both need a lot of sunlight to grow proficiently. each species rapidly grows taller, seeking to overshadow the other and monopolize access to sunlight. as they grow, their branches interlock, limiting the light available to the lower levels of the forest. 2. along a coastal shoreline, a flock of seabirds soars above the waves, while below them, a lone seal basks in the sun. as the seabirds dive into the water to catch fish, they create disturbances that drive small fish toward the surface. the seal, alert to these cues, positions itself strategically, ready to snatch up any fish propelled within its reach by the seabirds movements. 3. deep within a tropical rainforest, a vine wraps itself around the trunk of a towering tree, sapping nutrients and water from its host. as the vine grows, it weakens the host tree, gradually depriving it of resources and hindering its growth. despite the detrimental effects on the tree, the vine flourishes, using the tree as a support structure to reach sunlight in the upper canopy.

Explanation:

1. Competition: Both tree - species are vying for sunlight, a limited resource. Evidence: "Each species rapidly grows taller, seeking to overshadow the other and monopolize access to sunlight."
2. Commensalism: The seal benefits from the seabirds' actions of driving fish to the surface, while the seabirds are neither helped nor harmed. Evidence: "The seal, alert to these cues, positions itself strategically, ready to snatch up any fish propelled within its reach by the seabirds' movements."
3. Parasitism: The vine benefits by sapping nutrients and water from the tree, while the tree is harmed. Evidence: "A vine wraps itself around the trunk of a towering tree, sapping nutrients and water from its host. As the vine grows, it weakens the host tree, gradually depriving it of resources."

Answer:

1. Type of symbiotic relationship: Competition. Evidence: Each species rapidly grows taller, seeking to overshadow the other and monopolize access to sunlight.
2. Type of symbiotic relationship: Commensalism. Evidence: The seal, alert to these cues, positions itself strategically, ready to snatch up any fish propelled within its reach by the seabirds' movements.
3. Type of symbiotic relationship: Parasitism. Evidence: A vine wraps itself around the trunk of a towering tree, sapping nutrients and water from its host. As the vine grows, it weakens the host tree, gradually depriving it of resources.