The curse of the Halloween baby: women avoid giving birth on 'evil day' and Are Pregnant Women Subconsciously Avoiding Giving Birth on Halloween? A recent study comparing birth rates on Halloween vs. Valentine's Day suggests that pregnant women may be able to exert some subconscious control over the timing of parturition (i.e., when they give birth). It is possible that the negative connotations associated with Halloween may affect the mother's endocrine levels and thus affect the timing of labor as well; however, the potential mechanism is unknown.

Here on #SciAmBlogs, Cassie Rodenberg (Dear Dracula, Edward Cullen and Bill Compton: you have a substance abuse problem) and Eric Michael Johnson (A Natural History of Vampires) both blog about the association between vampires and various actual diseases such as rabies.

The Blogfather Bora blogs about how an upset in circadian physiology explains many symptoms of zombism in his post, Are Zombies nocturnal?

Just in time for Halloween: Vampires Dr. Doolittle has another take on the vampire/rabies situation by including an extra factor: vampire bats as vectors!

Brian at Dangerous Experiements discusses the physiology of the fear response in his post, How film makers are using your own imagination to scare you.

If you know of any other physiology-related Halloween posts from this weekend or today, send me the link via comment, email, or tweet, and I'll add them to the list!