Can a webcrawler execute a php script when it accesses a page?

I had a php page setup with just the code to send an email to several people. I went through the browser and put the page's address in the address bar to run it. Since then we've had this mystery going on with that same message being sent out randomly over 2 months or so. I ended up finding a record in our access log where Alexa was crawling the page at roughly the same time the emails were sent (within 3 min or less). I'm assuming that when it accessed the page to crawl it, the script ran the same way as if I would navigate to it in the browser.

So, does anyone know if that happens? I tried searching the internet but haven't come up with anyone else discussing the possibility.