Stephen Hedges
Stephen Blair Hedges (known as S. Blair Hedges) is Laura H. Carnell Professor of Science and director of the Center for
Biodiversity
Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic (''genetic variability''), species (''species diversity''), and ecosystem (''ecosystem diversity'') l ...
at
Temple University
Temple University (Temple or TU) is a public state-related research university in Philadelphia, Pennsylvania. It was founded in 1884 by the Baptist minister Russell Conwell and his congregation Grace Baptist Church of Philadelphia then calle ...
where he researches the
tree of life
The tree of life is a fundamental archetype in many of the world's mythological, religious, and philosophical traditions. It is closely related to the concept of the sacred tree.Giovino, Mariana (2007). ''The Assyrian Sacred Tree: A Hist ...
and leads conservation efforts in Haiti and elsewhere. He co-founded
Haiti National Trust.
Career
Hedges has a
Bachelor of Science
A Bachelor of Science (BS, BSc, SB, or ScB; from the Latin ') is a bachelor's degree awarded for programs that generally last three to five years.
The first university to admit a student to the degree of Bachelor of Science was the University o ...
undergraduate degree from
George Mason University, and a
Masters and
Ph.D.
A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...
in
Zoology
Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the animal kingdom, including the structure, embryology, evolution, classification, habits, and ...
from the
University of Maryland
The University of Maryland, College Park (University of Maryland, UMD, or simply Maryland) is a public land-grant research university in College Park, Maryland. Founded in 1856, UMD is the flagship institution of the University System of M ...
, supervised by
Richard Highton
Richard Highton (born December 24, 1927) is an American herpetologist, an expert on the biological classification of woodland salamanders.
Education and personal life
Highton was born in Chicago. His father encouraged his son to have an interes ...
.
Before he joined Temple University in 2014, he was a professor at
Penn State.
He is also a founding member of the NASA
Astrobiology Center. He has published over 300
peer-reviewed works including 10 books and monographs.
He was elected as a fellow of the
American Association for the Advancement of Science in 2009 for "revealing connections between biological evolution and Earth history in diverse groups of organisms", and was awarded the 2011 Penn State Faculty Scholar Medal for Outstanding Achievement in the Life and Health Sciences. A Cuban butterfly (''Leptodes hedgesi'' Schwartz & Johnson 1992), Cuban frog (''Eleutherodactylus blairhedgesi'' Estrada, Diaz, & Rodriguez 1997), and Cuban millipede (''Amphelictogon blairi'' Perez-Asso 1998) have been named in his honor.
Research
Hedges has studied the relationships and timing of major groups in the tree of life using genomic data.
This research has led to a number of discoveries including an early origin for the orders of placental mammals and modern birds, estimates of when
prokaryote
A prokaryote () is a single-celled organism that lacks a nucleus and other membrane-bound organelles. The word ''prokaryote'' comes from the Greek πρό (, 'before') and κάρυον (, 'nut' or 'kernel').Campbell, N. "Biology:Concepts & Conne ...
s and
eukaryotes first colonized land and its relevance for the planet, and the
phylogenetic
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
relationships of
reptiles and
insectivorous mammals. He has coined the word
timetree
TimeTree is a free public database developed by S. Blair Hedges and Sudhir Kumar, now at Temple University, for presenting times of divergence in the tree of life. The basic concept has been to produce and present a community consensus of the tim ...
for a phylogenetic tree scaled to time, co-founded the TimeTree database for exploring the time-scale of the tree of life, and co-edited the book ''Timetree of Life''. Hedges and his team produced a spiral
tree of life
The tree of life is a fundamental archetype in many of the world's mythological, religious, and philosophical traditions. It is closely related to the concept of the sacred tree.Giovino, Mariana (2007). ''The Assyrian Sacred Tree: A Hist ...
in 2015 to visualize the relationships over time of 50,000 species, and discovered that diversification and
speciation are both relatively constant through time and among groups.
Hedges also has a field program in the
Caribbean where he has studied the evolution and
biogeography of
amphibians and reptiles with genetic data and maintained a database of information on these species,
Caribherp. He discovered many new species in his work and has so far named 135 species of reptiles, amphibians, and butterflies. He also described three of the
smallest species of reptiles and amphibians, including the
Monte Iberia dwarf frog (''Eleutherodactylus iberia''), Jaragua gecko (''
Sphaerodactylus ariasae
''Sphaerodactylus ariasae'', commonly called the Jaragua sphaero or the Jaragua dwarf gecko, is the smallest species of lizard in the family Sphaerodactylidae.
Description
''Sphaerodactylus ariasae'' is the world's smallest known reptile. The s ...
''), and the
Barbados threadsnake (''Tetracheilostoma carlae''). Twelve articles in the ''
New York Times
''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid ...
'' have described his research.
Conservation
Work by Hedges and his team in Haiti has defined
hot spots of biodiversity leading to the establishment of three
national parks in Haiti. He also initiated a
captive breeding program to conserve ten
endangered species of frog at the
Philadelphia Zoo
The Philadelphia Zoo, located in the Centennial District of Philadelphia on the west bank of the Schuylkill River, is the first true zoo in the United States. It was chartered by the Commonwealth of Pennsylvania on March 21, 1859, but its openin ...
. Together with Haitian CEO
Philippe Bayard, he founded
Haiti National Trust, an environmental protection
NGO
A non-governmental organization (NGO) or non-governmental organisation (see spelling differences) is an organization that generally is formed independent from government. They are typically nonprofit entities, and many of them are active in h ...
.
Personal life
Hedges is interested in
Renaissance art
Renaissance art (1350 – 1620 AD) is the painting, sculpture, and decorative arts of the period of European history known as the Renaissance, which emerged as a distinct style in Italy in about AD 1400, in parallel with developments which occ ...
, which led him to conduct several scientific studies of early artwork, including the development of a method for dating old prints and a study on the historical biogeography of beetles based on the holes they bored in old books.
References
External links
*
{{DEFAULTSORT:Hedges, S. Blair
Living people
Evolutionary biologists
Pennsylvania State University faculty
Temple University faculty
American herpetologists
George Mason University alumni
University of Maryland, College Park alumni
Fellows of the American Association for the Advancement of Science
Year of birth missing (living people)
Place of birth missing (living people)