Monozygotic twins— more commonly referred to as identical twins— develop from a single fertilized ovum which then splits. In every 1000 births happening worldwide, 3 of them will be twins. Essentially, identical twins possess identical genetic makeup and are born the same sex. Physically, they often bear very strong resemblance to each other. They may also share a similar mentality, though they don’t always have identical personalities.
Throughout twins’ lives, their DNA changes slightly due to their environment. They may have certain preferences to specific surroundings or events because of their DNA. Twins raised in different households, because of adoption or other family changes, will often still have similarities. Behavior, hobbies, interests, and attributes. Scientists have found evidence within twins’ genes that prove that the aforementioned factors have a genetic impact. Because twins share identical genes, but are present in different surroundings, some events in their lives will still betray their similarity. Such as preference in jobs, hobbies, and friends.
Telling twins apart: twin DNA testing
Twin DNA testing enables twins to know if they are identical or fraternal by analyzing their DNA, comparing them together and confirming whether they have matching DNA profiles (in this case, they are identical) or non-matching DNA profiles (in this case, they are fraternal). Unlike a siblings DNA test, a twins test can provide no kind of indication regarding the parentage of the twins. A twins test is strictly there to compare the siblings’ profiles to confirm or exclude a match, thereby confirming whether they are identical or not. It is a siblings test that will tell you if the individuals tested have both parents in common or just a single parent in common.
For Kenny and Keith Lucas, identical twins who grew up together, their similarities don’t seem to end. They’ve both worked the same jobs, attended the same law school, and shared apartments. Now are comfortable with wearing identical clothing and accessories as they do their stand-up show “The Lucas Brothers”. Some twins may try to assist the public in telling each other apart, but it’s not every twin’s agenda.
More common than the identical twin is the fraternal twin. For every 1000 worldwide births, anywhere from 6 – 14 or more fraternal births will occur. Dizygotic twins— more commonly referred to as identical twins— are actually just two siblings who happened to develop and be born at the same time. Fraternal twins occur when two fertilized eggs are simultaneously implanted in their mother’s uterus wall. These eggs were fertilized by two different sperm cells. When eggs develop independently (but simultaneously) from the beginning, it will cause fraternal twins to be born. Fraternal twins are no more similar, from a point of genetics, to normal siblings.
Unlike identical twins, fraternal twins normally do not look extremely similar to each other. They will have the same casual sibling similarities, but aside from being the same age, they will generally have their own specific tastes and attributes.
Last year, a study discovered that there actually exists specific DNA that can influence whether a woman will give birth to fraternal twins. When previously it was thought that twin births were up to chance, it’s exciting to see recent scientific discoveries altering that information.
Twins in Different Cultures
Some cultures, such as the Bassa Nge tribe from Kogi state in Nigeria, celebrate twins and treat them reverence. Twins are seen as possessing special powers. Unlike other cultures, they view the first-born child as being younger than the second-born. For years, the Bassa-Nge people treated twins with extreme respect, even building shrines to them and giving them identical gifts.
In contrast, the Igbo speaking-people of southeast Nigeria once looked on the birth of twins with horror. Twins were seen as an evil omen from the gods. An omen that must be destroyed. Similarly, the Efik people from the same area of Nigeria also looked down on twins. They judged them so harshly that, for a long time, they put twins to death or abandoned them without further thought. In the late 1800s, Mary Slessor came to the area and began saving every abandoned twin she found.
In Western cultures, twins are seen as oddities. Sometimes good, sometimes bad. Aside from being used for research, twins generally live their own lives how they see fit. They have a heightened awareness of each other’s differences as well as similarities. And though they may be able to recognize and interpret each other’s microexpressions, twin telepathy doesn’t actually exist.
Sibling birth order and how it affects personality: The first-born child is the experiment. The parents had never been parents to a real child before. They try their utmost to not make mistakes. Schedules are maintained, attention is given, and parental teamwork is essential. Without other siblings around to look up to, the sole role model is the parent. The one person who is in charge of the child’s survival. And thus, perfectionism is born. Read more about sibling birth order and personality.
Finding Adoptive Siblings: When siblings enter adoptive or foster situations, they can’t always remain in the same household. Families interested in adding a single child to their home may not always be aware of the situation they are creating. Siblings may be split up even long before adoption, their lives now in the hands of the foster care system. Click here to read the full article.