Coming home one night, I approached the front door and found hundreds of earthworms crawling up the wall toward the artificial light. Some close to it were sort

Coming home one night, I approached the front door and found hundreds of earthworms crawling up the wall toward the artificial light. Some close to it were sort of tapping on the light. This was before ubiquitous cameras or else I'd have a picture. I haven't found info on this phenomenon anywhere, and this article doesn't offer any explanation of that. I'd like to recreate this, but it might have just been under the most perfect conditions.