Unlike adults, infants alternate between short waking periods and short naps. what can we infer about their neurotransmitters?

During the first one to two months of life, infants are incapable of deep sleep (they do not have trouble falling asleep but they do not generally stay asleep for very long stretches). This happens because infants can’t make the difference between night and day - they do not yet have a circadian rhythm. Around six weeks, the hormone melatonin is produced (pineal gland) and it helps establish a normal sleep-wake cycle.

Explanation:

The internal clock system in a newly born baby is not synchronized  with the 24 hour clock system of the real world and thus most of the newly born babies hardly sleep more than  4 hour at a time. The Circadian rhythms of  a fetus is synchronized with the mother's  heart rate and breathing when he/she is in womb. After birth a child has to develop its own circadian rhythms when exposed to sunlight and night frequently but this process takes time.

as the gila monster consumes the eggs or young of the desert cottontail and gambel's quail, thus its main food supply is only accessible for a restricted time duration every year. however, for this, the gila monsters exhibit three adaptations, which elevate their survival rate in the desert condition.  

first, is that they possess huge bodies, and can consume greater concentrations of food during a small period. secondly, they require to feed infrequently as they can accumulate fat in their tails. ultimately, their rate of metabolism is very low, so that they can burn their reservoirs of fat gradually.  

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.