What are pheromones?
Pheromones are scent-bearing chemicals released from sweat and other bodily fluids. Pheromones are known to be involved in sexual attraction in animals, and are also thought to affect sexual attraction in humans. Pheromones may also be involved in other types of sub-conscious chemical communication, called chemosignals, psychologist Bettina Pause said.
How do they work?
In animals, there is a specialized structure located in the nose called the vomeronasal organ (VNO) 
that can detect pheromones.
In humans, however, there are no nerves connecting this organ to the brain, making it useless, and in some people, it is not present at all.
Randy Reed of the John Hopkins School of Medicine said it is proven that some animals, such as pigs, can still sense and be affected by pheromones even when their VNO is blocked. It’s likely this is how humans can detect pheromones.
Study: Researchers at the University of Texas asked 21 women to wear two different shirts when sleeping: one while in the fertile time of their cycle and the other during their infertile time. The researchers then asked 21 men to pair with one woman and smell the two different shirts she wore to sleep. The men smelled the shirts and had to decide which one smelled better. The vast majority of men said the shirts worn by the fertile group were more “pleasant” and “sexy”. The dark half of the shirts above represent the shirt pairings in which the men felt the “fertile” shirt smelled better.
Smelling symmetry
Humans develop by splitting cells. If every cell division went perfectly, then babies would develop perfectly symmetrical. However, due to genetic mutations and environmental factors, perfect symmetry is nearly impossible. 
Biologist Randy Thornhill of the University of New Mexico said both men and women are more likely to choose a more symmetrical partner in order to produce offspring who are also more symmetrical and therefore “healthier.”
Study: Thornhill found that a woman can smell how symmetrical a man is. Women were asked to smell men’s undershirts and rate how attractive the man was on a 1 to 10 scale based on his smell. It was found that more symmetrical men smelled better than less symmetrical men.
The immune system and MHC
MHC (major histocompatibility complex) genes are an important part of immune system function. Because of pheromones, a woman can smell a man’s MHC genes. Researchers believe women prefer men whose MHC genes are different from their own because then their children would have a wider variety of MHC genes, and therefore have a healthier immune system. Women taking the birth control pill, however, are often more attracted to MHC genes that are similar to their own, possibly due to a hormonal change.
Read More
Cardinals survive five-set marathon against Central Michigan, advance to MAC Championship Final
By Daniel Kehn / 10 hours agoBall State advances to the MAC Championship with a five-set marathon victory over Central Michigan
Ball State women’s basketball falls to No. 16 UNC in the Battle 4 Atlantis
By Elijah Poe / 11 hours ago“I'm really glad that I was able to come back in time to play because we're not going to get this moment back,” senior Madelyn Bischoff said about the 63-52 loss to No. 16 North Carolina. “Even though we didn't win, I do think that this is really going to help us in the long run.”
3 takeaways from Ball State’s loss against UNC in the Battle 4 Atlantis
By Logan Connor / 12 hours agoBall State women’s basketball dropped its first contest of the season to UNC. Here are three takeaways from the 63-52 loss.
