Researchers studying guppies in trinidad found that guppies, in streams with high predation, reproduce earlier and more frequently. how would the scientists describe the selective force acting on the guppy population?

r- selection

Explanation:

Organisms respond to selection force by adjusting their reproduction rate, clutch size, and the age for reproduction. The species that acquire reproductive maturity earlier and reproduce at a faster rate are r-strategist and the selection force is r- selection. The members of these species are found in the habitat experiencing variations in climatic conditions, higher rates of negative ecological interactions such as predation.

These species produce a large number of offspring during one reproductive cycle and do not provide postnatal care to the young ones. According to the given information, the guppy population in the streams experience negative pressure of higher rates of predation. They adapt themselves to it by acquiring reproductive maturity at an earlier age and reproduce more frequently to ensure their survival.

"menstrual cycle is a complex cycle that consists of several processes. order of occurrence of steps in menstrual cycle are as follows:

1. high progesterone levels maintain the endometrium lining of the uterus.

2. endometrium lining breaks down and low levels of estrogen stimulate the pituitary to release fsh and lh.

3. fsh and lh stimulates the follicles to develop and the oocyte to produce estrogen.

4. rising estrogen levels suppress fsh production and development of other follicles.

5. a spike in lh causes follicle to rupture.

6. a breakdown of corpus luteum causes progesterone level to drop."