Answer: (A) Natural selection tend to reduce genetic variation as there was a smaller distribution of beak depths, but it tends to select for the most fit phenotypes, as there was an increase in average beak depth after the drought.
Explanation: The picture below shows proof if needed. On USATP
Answer:
Genetic Drift Is: variation in the relative frequency of different genotypes in a small population, owing to the chance disappearance of particular genes as individuals die or do not reproduce. How Cats Become Feral: Over time, a stray cat can become feral as her contact with humans dwindles. A stray cat may be socialized enough to allow people to touch her, but she will become less socialized—or even feral—if she spends too much time without positive interaction with humans.
<span>the large population becomes smaller.
also, bottleneck is when a large population quickly shrinks. the effects of genetic drift becomes much stronger.
e.g: seals
alleles can be lost during bottleneck and the number of alleles left can shift dramatically in just a few generations.</span>
Answer:
All of these are correct
Explanation:
According to the question, marble is a rock formed from limestone, which in turn is also formed from Calcite. This shows that marble is a kind of metamorphic rock because a metamorphic rock is any rock that is formed by the alteration of other rocks caused by heat, pressure or chemicals etc. These changes that occurs in the previously existing rocks are called METAMORPHOSIS.
Hence, since marble is formed from limestone, it concludes that marble is a metamorphosed rock formed from a previously existing limestone rock. Also, since Calcite, a precursor of limestone that marble is formed from can be degraded by acids, both limestone and marble which are formed from it will also be dissolvable by acids.