Transcript Twins Study PowerPoint

Nature vs. Nurture - Twin Studies.
STEPHANIE PRECIADO
Identical twins
 Identical twins are formed when one fertilized egg divides into
two separate embryos to make two babies.
 The two embryos can share a single placenta and can be in the
same or different sac.
 Since identical twins come from the same fertilized egg, they
have the exact same DNA.
 They are always the same sex and they have the same blood
type and can have the same finger tips
Fraternal Twins
 Fraternal twins make up approximately 75% of the twin
population and can be boy/boy, girl/girl, or boy/girl sets.
 Fraternal, or "dizygotic"
 Fraternal twins are two separate eggs fertilized by two separate
sperm to form two separate embryos and then make two
separate babies.
 The genetic makeup of dizygotic twins is different, so they are
not identical. these twins share half of their genes, just like any
other pair of siblings.
How are identical twins similar and different?
 Identical twins have the same DNA therefore they
will have physical and other similarities
 they can also look different from one another.
 The environment in which they were in when they
were in the womb can cause the twins to be different.
 The environment in which they grew up in once they
were born can also be a factor in why they are
physically different.
How are fraternal twins similar and different?
 Fraternal twins are different because they most likely
came from 2 fertilized eggs and only share 50% of
their DNA
 Fraternal twins can be no more alike than siblings
born years apart.
 They can also be close to identical in their looks.
Why are identical twins so much alike?
 Identical twins are very alike because they have the
same DNA
 Twins that were separated at birth still are very
similar even though they were raised in different
environments
What psychologist have studied twins?
 Francis Galton is a psychologists that studied twins.
 He studied the effects of nature and nurture on
twins.
 In the experiments he would do, he would study
identical and fraternal twins
 he did his research on twins based on whether they
grew up together or not and if they were ever alike.
 He studied how long it took before they started
becoming different, why the became different or why
they were never alike.
Nature Vs. nurture
 The concept of nature vs. nurture is whether twins are the
way they are because of their DNA (nature) or if its because
of their environment (nurture).
 This can begin from within the womb because the
environment in which the mother is in affects how the
twins develop in the womb.
 Experiments used to prove whether its nature or nurture
are mostly done with twins separated at birth.
Nature - Identical/fraternal twins
 Nature on fraternal twins:
 Because fraternal twins only share half of their DNA, their
personalities wouldn’t be much the same just like their looks.
 They would be more different at a young age and also as they
grow older.
 Nature on identical twins:
 Identical twins would be very similar because their DNA is the
same.
 They would look the same and would change as they grow but
most likely will still do many things alike.
Nurture – identical/fraternal twins separated
 Nurture on fraternal twins:
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The environment in which the twins grow up in would also affect
what they do in life because it would show them good and bad ways
of life.
These twins could be separated and grow up in different
environments but would still have similarities because of the genes
they share but the environments affect would still be present.
 Nurture on identical twins:
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Nurture on identical twins doesn’t show as much because they are
very alike.
Because identical twins DNA is the same they will almost always
have more than a few things in common that they do even if they
grew up apart in completely different environments.
Nature vs. nurture twins separated at birth
 The stories told about twins separated at birth can be
very surprising because they can prove that both
nature and nurture take part in why they are alike
and different.
 In the picture below you can see how nature and
nurture took affect in the women's looks even though
they were raised apart.
Nature vs. nurture twins raised together
 Stories about twins that grew up together also proves
that nature and nurture have a part in why they are
so much alike and also why they are different.
 In this picture you can see how nature took a
stronger effect than nurture in their looks and their
environment on the way they dress
Nature vs. nurture twins seperated at birth
 James Arthur Springer and his
identical twin, James Edward
Lewis
 these twins had met before
they were called into meet by
the university.
 Yet they showed signs of the
same personalities, behaviors,
and attitudes when tested
individually.
 some similarities between
these twins are their names, ex
wives names, pets names,
children’s names and some of
their likes and dislikes.
Nature vs. nurture twins separated at birth
 Daphne Goodship and Barbara Herbert
 met when they were 40. Debbie was raised Jewish and
Sharon was raised Catholic.
 “We discovered we had a miscarriage the same year,
followed by two boys and a girl in that order,” says Barbara.
 they laugh and fold their arms the same way.
Nature vs. nurture separated at birth
 Debbie and Sharon
 Debbie Mehlman and Sharon Poset were both raised under different
traditions and faiths. However they were still very similar.
 They would both cross their eyes when they became excited.
 Segal the person that reunited them did an experiment on how they
moved and said “…they can’t see each other, but they’re moving the
same way.”
 There were some differences between the twins like Debbie likes to
work out but Sharon felt she didn’t need to.
Twins similarities after being reunited
 All the twins that were in the experiments above had many
similarities that were physical and in their likes and their
lives
 Some of the similarities the twins shared were their names,
jobs, same amount of children and they named them the
same.
 Even though they were separated for so long, their genes
still took a part in them and made them alike.
Works cited
 Classics in the History of Psychology - Galton (1875). (n.d.). Classics in the
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History of Psychology - Galton (1875). Retrieved November 7, 2013, from
http://psychclassics.yorku.ca/Galton/twins.htm
Differences and Similarities Between Twins. (n.d.). Differences and
Similarities Between Twins. Retrieved November 7, 2013, from
http://psychproject8.tripod.com/id2.html
Driscoll, K. (2007, November 1). Two of a Kind: A Study of Identical Twins
and the Environment. Two of a Kind: A Study of Identical Twins and the
Environment. Retrieved November 7, 2013, from
http://serendip.brynmawr.edu/biology/b103/f05/web1/kdriscoll.html
Facts About Fraternal Twins. (n.d.). Facts About Fraternal Twins.
Retrieved November 7, 2013, from
http://www.multipletreasures.com/facts-about-fraternal-twins.php
Flais, S. (2013, May 11). The Difference Between Identical and Fraternal
Twins. HealthyChildren.org. Retrieved November 7, 2013, from
http://www.healthychildren.org/English/family-life/familydynamics/pages/The-Difference-Between-Identical-and-FraternalTwins.aspx
Works cited
 Heredity Versus Environment: Twin, Adoption, and Family Studies. (n.d.). Twin,
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Adoption, and Family Studies. Retrieved November 7, 2013, from
http://www.personalityresearch.org/papers/haimowitz.html
IDENTICAL TWINS: PINPOINTING ENVIRONMENTAL IMPACT ON THE
EPIGENOME. (n.d.). Identical Twins: Pinpointing Environmental Impact on the
Epigenome. Retrieved November 7, 2013, from
http://learn.genetics.utah.edu/content/epigenetics/twins/
NEVER SAY ALWAYS. (2009, October 8). NEVER SAY ALWAYS. Retrieved
November 7, 2013, from http://lornareiko.wordpress.com/2009/10/08/identicaltwins-who-were-separated-at-birth-what-are-they-like/
beetle. (n.d.). Identical Twin Studies and Evolutionary Psychology. Identical Twin
Studies and Evolutionary Psychology. Retrieved November 7, 2013, from
http://drbeetle.homestead.com/twins.html
dizygotic twin. (n.d.). Encyclopedia Britannica Online. Retrieved November 7,
2013, from http://www.britannica.com/EBchecked/topic/217570/dizygotic-twin
winerman, l. (n.d.). A second look at twin studies. http://www.apa.org. Retrieved
November 7, 2013, from http://www.apa.org/monitor/apr04/second.aspx