Archaeologist: The extensive network of ancient tracks on the island of Malta was most likely created through erosion caused by the passage of wheeled vehicles.
Conclusion (most likely)
The big network of tracks on Malta was probably created by wheeled vehicles eroding these paths.
Intermediate Conclusion
Even though some people think the tracks were manually cut, the uniformity to the depth of the track is more likely indicative of wheel diameter.
Evidence
Routes would get used until the the wheel had eroded to a depth that made further vehicle usage impossible.
Evaluate
Whenever we're doing Main Conclusion and Role, we remind ourselves prior to reading the paragraph that these questions love to put the Conclusion earlier than the Evidence. We start listening in the first sentence to hear if it's an opinion belonging to the author. If it is, then that's almost always the Conclusion.
The opinion indicator "most likely" shows us that this first sentence is a speculative opinion. Does our author proceed to try to support this claim? Yes, the rest of the paragraph is trying to defend the idea that these tracks are from wheeled vehicles.
The two big patterns with Main Conclusion are: 1. Conclusion is the first sentence 2. Conclusion is some rebuttal (usually after a but, yet, however)
So they are trying to use these tendencies against us here by wanting us to zoom in on the Intermediate Conclusion introduced by "However".
But that conclusion still serves to support the first sentence.
Goal
Look for something that means the same as the first sentence: the tracks were probably created through erosion from wheeled vehicles going through.