The STR fragments will have different size for different animals.
Explanation:
STR means Short Tandem Repeats.
STR forms the genome's microsatellite region.
STR or microsatellite is that region of the genome where, about two to seven base pairs of the DNA (for example, ATGATGATGATG), are repeated for multiple time. Such sequences can have few hundred repeats.
While replicating these micro-satellite regions, the accuracy of the DNA polymerase in proof-reading the sequence of the newly synthesised strand, decreases, due to the multiple repeats.
As a result of this, the DNA polymerase either adds more or adds less of such repeated sequences as compared to the parental DNA sequence. This results in generation of polymorphism (different microsatellite size in different individuals) in the repeat regions.
Due to difference in size of the STR in different individuals, the size of the fragment amplified through PCR will vary for different elephants.
The effects of a drought on flow in streams and reservoirs may not be noticed,and water levels in wells might not reflect a shortage of rainfall for a year or more after a drought begins.
