The spiders that survived the first pesticide spraying were resistant to the pesticide and when they reproduced most of their offsprings got the gene of pesticide resistance.
Think of it like this. Horses do a LOT of galloping, which is hard on the feet! Hooves are a physical ADAPTATION, so that the horses won't experience pain on their journeys. They're hard, so that the horses don't feel the ground nearly as much. Now, mountain goats travel over rough terrain, with sharp rocks and steep inclines. Again, it's really easy for them to get hurt strutting around the mountains, so they evolved hard hooves to protect their feet.
Answer:
Homologous structures are structures that are similar in related organisms because they were inherited from a common ancestor. These structures may or may not have the same function in the descendants. Figure below shows the hands of several different mammals. They all have the same basic pattern of bones
An environmental group claims that a local chemical plant is polluting a nearby river. They are calling for a shutdown of the chemical plant. The evidence that would help you the most in evaluating the claim would be (A) a repeated study that shows chemicals produced by the plant are in water harming fish or other wild life. (The answer is A.)
