Hans Asperger (1906-1980)Hans Asperger studied mental abnormalities in children in
Vienna, Austria, in the early twentieth century. Asperger was one of
the early researchers who studied the syndrome that was later named
after him, Asperger's Syndrome. Asperger described the syndrome in
his 1944 publication
Die Autistischen Psychopathen im
Kindesalter (Autistic Psychopathy in Childhood). At that time,
the syndrome was called autistic psychopathy, and Asperger noted
that characteristics of the syndrome included lack of sympathy,
one-sided conversations, and difficulty forming friendships.
Asperger's work led to the recognition of Asperger's Syndrome as a
disorder that results from abnormal development, and the syndrome was later
classed on the autism spectrum.
Skinner v. Oklahoma (1942)In 1942, the United States Supreme Court Case of
Skinner v. Oklahoma ruled that states could not legally sterilize those inmates of prisons deemed habitual criminals.
Skinner v. Oklahoma was about the case of Jack Skinner, an inmate of the Oklahoma State Penitentiary in McAlester, Oklahoma, who was subject to
sterilization under the Oklahoma Habitual Criminal Sterilization Act of 1935. The case, decided on 1 June 1942, determined that state laws were unconstitutional if those laws enabled states to forcibly sterilize inmates deemed to be habitual criminals. Such laws violated the
Equal Protection Clause of the Fourteenth Amendment to the US Constitution. The
Skinner v.
<a href="/search?text=Aristotle" title="" class="lexicon-term">Aristotle</a> (384-322 BCE)Aristotle studied developing organisms, among other
things, in ancient Greece, and his writings shaped Western
philosophy and natural science for greater than two thousand years.
He spent much of his life in Greece and studied with Plato at
Plato's Academy in Athens, where he later established his own school
called the Lyceum.
Aristotle wrote greater than 150 treatises
on subjects ranging from aesthetics, politics, ethics, and natural
philosophy, which include physics and biology. Less than fifty of
Aristotle's treatises persisted into the twenty-first century. In
Julia Barlow Platt (1857-1935)Julia Barlow Platt studied neural crests in animal embryos and became involved in politics in the US during the nineteenth and twentieth centuries. She researched how body and head segments formed in chicks (
Gallus gallus) and spiny dogfish (
Squalus acanthias). Platt observed that in the mudpuppy (
Necturus maculosus), the coordinated migration of
neural crest cells in the embryo produced parts of the nervous system, bones, and connective tissues in the head.
The Hedgehog Signaling Pathway in <a href="/search?text=Vertebrates" title="" class="lexicon-term">Vertebrates</a> The hedgehog signaling pathway is a mechanism that
regulates cell growth and
differentiation during embryonic
development, called
embryogenesis, in animals. The hedgehog signaling pathway
works both between cells and within individual cells. The hedgehog
gene (
hh) was observed in fruit flies (
Drosophila
melanogaster) in 1980, and later in vertebrates in 1993.
Unlike flies, which have one
hh gene, vertebrates have
several
hh genes. The hedgehog signaling pathway controls a
Mary Coffin Ware Dennett (1872–1947)
Mary Coffin Ware Dennett advocated for social reform in the United
States in the early twentieth century, particularly regarding sex education and women's
rights to access
contraception. Dennett authored
several publications on sex education and
birth control laws. She also
worked to repeal the Comstock Act, a federal law that made it
illegal to distribute obscene materials through the US Postal
Services. During the early 1900s, Dennett distributed a pamphlet she
wrote on sex education called, "The Sex Side of Life," through the
post, which triggered a series of legal challenges that contributed to
the dismantling of the Comstock Act. Dennett was an advocate for sex
Estrogen and the Menstrual Cycle in Humans
Estrogen is the primary sex
hormone in women and it functions during the
reproductive menstrual cycle. Women have three major types
of
estrogen: estrone,
estradiol, and estriol, which bind to and
activate receptors within the body. Researchers discovered the three
types of
estrogen over a period of seven years, contributing to more detailed descriptions of the menstrual cycle. Each type of
estrogen
molecule contains a slightly different arrangement or number of atoms
ABO Blood Type Identification and Forensic Science (1900-1960)The use of blood in forensic analysis is a method for identifying individuals suspected of committing some kinds of crimes. Paul Uhlenhuth and Karl Landsteiner, two scientists working separately in Germany in the early twentieth century, showed that there are differences in blood between individuals. Uhlenhuth developed a technique to identify the existence of antibodies, and Landsteiner and his students showed that
humans had distinctly different blood types called A, B, AB, and O. Once doctors differentiated blood into distinct types, they could use that information to safely perform blood transfusions. Furthermore, forensic scientists can use that information to exculpate people suspected of some types of crimes, and they can use it to help determine the paternity of children.
Kurt Benirschke (1924-)Kurt Benirschke studied cells, placentas, and endangered species in Germany and the US during the twentieth century. Benirschke was professor at the University of California in San Diego, California, and a director of the research department at the San Diego Zoo in San Diego, California. He also helped form the research department of the San Diego Zoo and its sister
organization, the Center for Reproduction of Endangered Species.
George McDonald Church (1954-)George McDonald Church studied DNA from living and from
extinct species in the US during the twentieth and twenty-first centuries. Church helped to develop and refine techniques with which to describe the complete sequence of all the DNA nucleotides in an organism's
genome, techniques such as
multiplex sequencing, polony sequencing, and nanopore sequencing. Church also contributed to the Human Genome Project, and in 2005 he helped start a company, the Personal Genome Project. Church proposed to
use DNA from extinct species to clone and breed new organisms from
those species.
