How much energy is passed on to each trophic level

Plants that have reproductive structures called cones are?

Matthew decided he wanted to hike up mount everest. on his way to the top, it began to snow and the temperature dropped to -10°f. matthew forgot to wear a heavy jacket so his body began to shiver beyond control. in this case, matthew's body shivering is the to a drop in temperature. * 0 points reflex stimuli responce environmental facto

In general, characteristics that an organism survive and reproduce become more common over time. what mechanism of evolution causes this?