#1 - Sea turtle hatchlings leaving their hatching grounds on Florida

[Administrator]

Please post your questions below!

[saiffshaikhh@gmail.com]

Please post your questions below!

Could you explain the sentence the last sentence before the question stem? I was able to get the answer but through process of elimination. I narrowed it down to B and C because I felt that those were the only ones that related to the passage.

[Amber Thomas]

Hi Saiffshaikhh!

Let's break down our stimulus:

Premise 1: Florida sea turtle hatchlings reach ocean currents by swimming to the northeast, defined by earth's magnetic field.
Premise 2: Florida hatchlings placed in a large indoor tank also swim towards the northeast.
Premise 3: When the tank is surrounded by a strong magnetic field in the opposite direction, the hatchlings swim in the opposite direction that they would without the artificial magnetic field (i.e. southwest instead of northeast).

So, from our premises, it would appear that turtle hatchlings use magnetic fields for their sense of direction. We know this because both in the ocean and in tanks, they swim northeast (as dictated by magnetic poles). When their magnetic field is artificially disrupted and reversed, they swim in the opposite direction that they would normally. This would lend credence to the thought that hatchlings are reliant on magnetic fields for their sense of direction.

I hope this helps!