While observing some ants, a group of German scientists noticed that the ants had an excellent sense of distance. Wondering how this was possible, they decided to perform an experiment.

First, the scientists taught ants to retrieve food from a feeder placed near the ants' home. Then, they removed the lower portion of some of the ants' legs to make them shorter. They also attached tiny stilts to some of the other ants' legs to make them longer. Finally, the scientists watched the altered ants attempt to retrieve food from the feeder.

After several trials, the scientists found that the ants with shortened legs walked toward the feeder but stopped short of it. On the other hand, the ants with lengthened legs walked past the feeder.

Which of the following conclusions can be made given this information?