Tag Archives: fraternal twin


By: Katie Kirkman

Identical twins are monozygotic and they are one of a pair of twins that develop from a single fertilized ovum and therefore they are the same sex, have identical features, and possess the same set of 46 chromosomes. Although many people don’t know the differences between identical and fraternal twins and believe they are developed the same way, they are most definitely developed completely different. Fraternal twins are dizygotic and they do not necessarily resemble each other or the same sex because they develop from two separately fertilized ova while identical twins develop from the same fertilized ova.

Twins has a lot to do with my family because I am an identical twin with my sister and also my brothers are fraternal twins. The odd thing is that there is absolutely no history of twins in my family and usually when there is a family history of twins the family is most likely to have them. My sister and I are very similar when it comes to personality, features, and interests. On the other hand, my brothers are pretty much polar opposites of each other.

My sister and I both have very similar features with blond hair, same height, freckles and blue eyes. Although a lot of our close friends and family seemed to figure out a way to tell us apart and believe that we no longer look alike, people that just met us have a lot of difficulty figuring it out. Not only do we look alike, but also all throughout elementary school, middle school, and high school we had the same group of friends and had same interests. We both played soccer and we loved the same television shows. Although we decided to attend different colleges, we are pursuing the same major and looking for the same career in the future, which is physical therapy.

My brothers growing up had the same group of friends generally but they had completely different personalities, features, and interests.  One of my brothers had red hair and freckles, while the other one has brown hair and no freckles. Also, one is a lot taller than the other. They both have different interests as one played soccer and is pursing a major of engineering, and the other played hockey and is pursing a major of business. I also believe that their personalities are very different and opposite of each other as one is easier going and one is a little more serious.

Growing up my sister and I were best friends and always did everything together while my brothers tended to have a lot of arguments and occasionally hung out together with their friends. It was interested learning about twins in the class and to see the differences between fraternal and identical twins.

“Identical Twin.” Dictionary.com. Dictionary.com, n.d. Web. 06 Mar. 2014. <http://dictionary.reference.com/browse/identical%2Btwin>.

“Fraternal Twin.” Dictionary.com. Dictionary.com, n.d. Web. 06 Mar. 2014. <http://dictionary.reference.com/browse/fraternal%2520twin

Type of Twins

My cousins are twins. They are both girls, look very similar, and have similar personalities. Growing up though my family and I had our doubts that they were identical. They both have blond hair and blue eyes, most people can’t tell them apart. But I always could and so could the rest of my family, except of my little sister, who mixes them up every time. So, they look a lot alike but they don’t look identical. They have different shoe sizes and one of the twins has more freckles than the other.

But then they also have very similar personalities. They have always played the same sports, had the same friends, and now both are pursuing a medical career at the same college, where they are both in sororities. When they are doing their own things, both tend to ask as leaders, helping others, yet put them in the room together and one always dominates and becomes the leader. At every family event, I have always noticed the same twin taking charge. If you separate them though they both take charge. Also sitting next to both of them I found one to be more sympathetic and the other more outgoing. These differences are only distinguishable when they are separated though.

So are my cousins identical or fraternal twins? Identical twins, or monozygotic twins, occur when a fertilized egg splits, creating two of the same organism. These types of twins share the same DNA and because of that are very similar. Fraternal twins, or dizygotic twins, on the other hand, come from two different eggs and two different sperm. This causes the twins to be different. They do not share the same DNA. Fraternal twins are no more alike, genetically, than other siblings, they were just born at the same time.

Learning about these differences in definition I now strongly believe my cousins are identical twins, they are too similar not to be. The differences they have that allow me to distinguish them have come from various environmental effects. Each twin has had different experiences and therefore has become their own person. One of them had a concussion while the other did not. In addition one studied in Denmark for a few weeks while the other did not. Events like these have shaped my cousins differently, so even though they are identical, they are each their own person with a unique life.