Ddt was once considered a "silver bullet" that would permanently eradicate insect pests. today, instead, ddt is largely useless against many insects. what would need to be true for pest eradication efforts to have been successful in the long run?

4. None of the individual insects should have possessed genomes that make them resistant to DDT

Explanation:

DDT became ineffective in the eradication of insect pests because insects evolved by natural selection.

Some insects had genes that made them to be resistant to the effects of DDT. Hence, these few usually survive whenever DDT is applied to their environments. The few surviving ones thus reproduce in the environment, pass the DDT-resistant gene on to their offspring and give rise to a population of insect that are resistant to DDT.

Hence, if none of the earlier insects possessed the DDT-resistant gene, it would not have been possible for the insect population to evolve and pest eradication efforts using DDT would have been successful in the long run.

The correct option is option 4.

endo:

regulates body hormones, aldosterone, vasopressin

neural:

signal, regulates body using electric signals, reflex

endo has to do with hormones; aldosterone and vasopressin are both hormones. i also had this question and got it right : d

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands