1, some old yards can really distinguish nests according to the environment and buildings at that time. When most swallows return to China, they can really find out where the tides of their own buildings are according to the local buildings, and some of them are old-fashioned. They can really know the houses built before and will build their own nests next to their old houses, which is in line with their habits.
2. When most swallows come back, there is actually no way to accurately find the nest they have seen before. In real life, even if swallows come back, they still can't tell the nest they built in the past, and because the environment in the disaster-stricken areas has changed a lot, even if the previous nest still exists, they still have to rebuild it, so most swallows can't tell the specific location of their previous nest.
3. When looking back, some eyes can really identify the location of the nest they saw before through the environment. Generally speaking, when swallows come back, some old yards can really identify the general orientation of their former nests through the surrounding environment, but according to scientists, they can find their nests according to their own smells and past experience, but most swallows have no ability to identify their former nests, so they just know a location and rebuild their houses by themselves.
Generally speaking, whether swallows can identify the nests they built in the past needs detailed investigation, and most swallows only remember a specific location, so they can't know the specific nest area and where they built in the past, but some old swallows can find their nests by memory.