Mammals vs Fish Logic
Why must a sea lion return to land or the surface regularly?
It needs to breathe air.
Which whale group uses echolocation to locate prey?
Toothed whales.
Which organism provides the original energy source for most marine ecosystems?
Phytoplankton.
Why do many marine predators attack weak or injured prey?
They require less energy to capture.
Where do most seals give birth?
On land or ice.
A shark and a dolphin have similar body shapes. What explains this similarity?
They evolved similar adaptations for swimming, not because they are closely related.
Why can blue whales survive without chasing individual fish?
They consume enormous amounts of krill through filter feeding.
Why can removing one species affect many unrelated species?
Food webs are interconnected.
Why might prey suddenly stop swimming instead of fleeing?
Remaining still can reduce detection.
Why do many seal mothers fast while nursing pups?
They rely on stored body fat.
Why do whales have tail flukes that move up and down instead of side to side like fish?
They evolved from land mammals.
Why would echolocation be especially useful in deep ocean habitats?
Light is limited underwater.
If squid populations crash, which marine mammals would likely be affected first?
Squid-eating predators such as sperm whales.
Why would a predator abandon a chase after only a few seconds?
Continuing may cost more energy than the prey is worth.
Why do many pinniped pups have a fluffy white coat at birth?
It provides insulation before entering the water.
A marine animal has lungs but no visible fur. Why can scientists still classify it as a mammal?
Mammals do not need visible fur if they share other defining traits.
Why are baleen whales generally unable to bite large prey into pieces?
They lack functional teeth.
Why are top predators especially vulnerable to disruptions lower in the food web?
They depend on energy passed through multiple trophic levels.
How can ocean currents interfere with a predator's hunting success?
They can disrupt scent trails or prey movements.
Why do male elephant seals fight during breeding season?
To gain access to mates.
Scientists discover an aquatic species with lungs, live birth, and hair as a fetus but scales as an adult. Which evidence would be strongest for classifying it as a mammal?
Nursing its offspring with milk.
A fossil whale has both teeth and primitive baleen structures. What does this most likely represent?
A transitional stage in whale evolution.
A disease wipes out half the zooplankton population. What long-term effect would most likely occur?
Declines in organisms that depend on zooplankton and their predators.
Two predators catch the same amount of prey, but one expends much less energy. Which is likely to have greater long-term survival?
The more energy-efficient predator.
A female seal delays returning to the ocean until her pup has doubled in weight. What reproductive advantage does this provide?
A larger pup has a better chance of surviving after weaning.