<em>The exposure of sea bed or undersea surface is called sea-level regression.</em>
<u>Explanation:</u>
Sea-level regression occurs when sea level drops down due to several climatic changes. This triggers extinction of several species. There had been several mass extinctions in the past due to <em>sea-level regression.
</em>
<em>Chances of survival of shallow</em> water species become feeble when the sea level falls. In the case of mass extinctions regression can be seen as a symptom and not a cause.
Marine transgression is the opposite <em>phenomena of regression</em> where sea level rises and covers the land which was previously above the sea level.
The feature that you need to use in examining and make a
determination whether the skeletal remains in the pelvis is either male or
female is by analyzing its size and construction. It is because males have
larger pelvis bone and are robust elements compared to females who have smaller
and are light in terms of construction.