Why Do We Have Two Nostrils?

TL;DR

We have two nostrils because one nostril inhales air better and faster than the other, allowing us to smell more things. Space smells like burning and astronauts have reported a strange metallic smell after being in space. Our sense of smell is closely tied to memories and emotions.

Transcript

Hey, Vsauce. Michael here. And our faces have a lot of holes. We have two ears and two eyes. It makes sense, because the difference in time it takes for a sound to reach one ear and the other, allows us to localize where the sound is coming from. And having two eyes gives us two slightly different perspectives that we can put together in order to p... Read More

Key Insights

• 🥳 Our sense of smell relies on having two nostrils, with one nostril dominant at different times of the day for better odor absorption.
• 👾 Space itself doesn't have a smell, but objects that have been in space and returned to Earth have a distinct metallic burning smell caused by high-energy particles reacting with the air.
• 👃 Our sense of smell is closely connected to memories and emotions, and can instantly trigger memories when we encounter certain odors.
• 🤨 Our sense of smell may be a natural way to avoid inbreeding, as individuals raised together tend to be less physically attracted to each other later in life.
• 👃 Anosmia is the word for the inability to smell, and olfactory refers to the sense of smell.
• 👃 Smells are not intrinsic to molecules, but rather a consequence of how they react with our olfactory receptors.

Questions & Answers

Q: Why do we have two nostrils instead of just one big hole in our nose?

Having two nostrils allows us to smell more things because different odors are absorbed by our skin and snot at different rates. It helps with localizing and perceiving different smells.

Q: What does space smell like?

Space itself doesn't have a smell because it is a vacuum. However, objects that have been in space and returned to Earth have a distinct metallic burning smell caused by high-energy particles reacting with the air.

Q: How are our sense of smell and memories connected?

Our sense of smell is closely tied to the limbic system in the brain, which is involved in emotions and memories. Smelling certain odors can instantly trigger memories of where and when we first encountered that smell.

Q: Why do individuals raised together tend to be less physically attracted to each other later in life?

This is known as the Westermarck effect, and it may be a natural way to avoid inbreeding. Our olfactory system allows us to distinguish the smell of a stranger from someone we are genetically related to or grew up with, reducing the likelihood of inbreeding.

Summary & Key Takeaways

• Our sense of smell relies on having two nostrils, with one nostril inhaling air better and faster than the other, allowing us to smell a wider range of odors.

• Space itself doesn't really have a smell, but objects that have been in space and brought back to Earth have a distinct metallic burning smell.

• Our sense of smell is closely tied to memories and emotions, and smelling something can instantly trigger memories of where and when we first encountered that smell.