The diagram below shows the layers of a rock having an ammonite: a rock columns labeled rock is shown. the column has three layers. the bottommost layer of the rock has one shaded circle, the middle layer has a two squares, the top layer has one star shape along with two identical organisms labeled ammonite in the key. a key is shown on the right of the diagram. the shaded circle is marked as x, the square is marked as y and the star is marked as z which statement about the rock fossils is true? fossil y is older than fossil x. fossil z is younger than fossil y. fossil z existed over many periods of time. fossil y existed during the same period as the ammonite.

Fossil Z is younger than Fossil Y.

Explanation:

For any age-related questions in geology, we have to consider the basic principle of stratigraphy. According to which, sediment layers on top harbor younger fossils whereas layers on the bottom have older fossils. In the case given here, Fossil Z is younger because it is in the top layer and Fossil Y is in the middle layer. The other two options are completely wrong because Fossil Y cannot be older than Fossi X and likewise, Fossil Z doesn't exist in multiple periods rather it is present only once.

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.