No, dinosaurs did not exist in the pre-cambrian period
Population of older female elephants different from the younger female elephants is described below.
Explanation:
- THE OLDEST ELEPHANTS wandering Mozambique’s Gorongosa National Park bear the indelible markings of the civil war that gripped the country for 15 years: Many are tuskless. They’re the lone survivors of a conflict that killed about 90 percent of these beleaguered animals, slaughtered for ivory to finance weapons and for meat to feed the fighters.
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Hunting gave elephants that didn’t grow tusks a biological advantage in Gorongosa. Recent figures suggest that about a third of younger females—the generation born after the war ended in 1992—never developed tusks. Normally, tusklessness would occur only in about 2 to 4 percent of female African elephants.
- New, as yet unpublished, research she’s compiled indicates that of the 200 known adult females, 51 percent of those that survived the war—animals 25 years or older—are tuskless. And 32 percent of the female elephants born since the war are tuskless.
- A male elephant’s tusks are bigger and heavier than those of a female of the same age, says Poole, who serves as scientific director of a nonprofit called ElephantVoices. “But once there’s been heavy poaching pressure on a population, then the poachers start to focus on the older females as well,” she explains. “Over time, with the older age population, you start to get this really higher proportion of tuskless females.”
- “The prevalence of tusklessness in Addo is truly remarkable and underscores the fact that high levels of poaching pressure can do more than just remove individuals from a population,” says Ryan Long, a behavioral ecologist at the University of Idaho and a National Geographic Explorer. The “consequences of such dramatic changes in elephant populations are only just beginning to be explored.”
The answer is option A.
The gonads of the male and
female body are regulated by Folicle-stimulating hormone (FSH) and
Luteinizing (LH) from the pituitary glandule. In males, FSH stimulates
production
of sperm cells while in females it stimulates the
growth of the ovum. And LH, in males, stimulates the Leydig cells in
order to produce testosterone, and in females, stimulates
hormones preparing the body for pregnancy, as well as playing an important role in ovulation.
