I believe there is some heritability. What's more, long term human couples tend to have dissimilar immune systems [0], allowing their offspring to have a more diverse spread of immunities.

The fact that humans are somehow able to _detect_ properties of a potential partner's immune system is super interesting to think about.

[0] - https://www.amazon.com/Social-Animal-Sources-Character-Achie...

Forget about the spammy title, this is an amazing book on copy writting:

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I'm currently reading this one, so far so good:

Moonwalking with Einstein: The Art and Science of Remembering Everything http://amzn.to/nGEnkv

This is a small list of books I want to read:

The Secret Life of Pronouns: What Our Words Say About Us http://amzn.to/oiEIDs

Willpower: Rediscovering the Greatest Human Strength http://amzn.to/qTNpgB

Do More Faster: TechStars Lessons to Accelerate Your Startup http://amzn.to/njSDPh

The Social Animal: The Hidden Sources of Love, Character, and Achievement http://amzn.to/okuaFh

The Power of Full Engagement: Managing Energy, Not Time, Is the Key to High Performance and Personal Renewal http://amzn.to/rptuZ9

The Upside of Irrationality: The Unexpected Benefits of Defying Logic at Work and at Home http://amzn.to/oaIDgu