Textbook Notes (363,135)
Canada (158,215)
York University (12,357)
Biology (941)
BIOL 1001 (162)
Tamara Kelly (110)


2 Pages
Unlock Document

York University
BIOL 1001
Tamara Kelly

Phylogenetic's - Bio 1001 (p 8 -9) 1.4 The Tree of Life • Over the past several decades, biologists have also documented dozens of cases in which natural selection has caused populations of one species to diverge and form new species The divergence process is called speciation • • speciation has 2 important implications: all species come from pre- existing species; and all species past and present, trace ancestry back to a single common ancestor • tree of life; a family tree of organisms • If life on Earth arose just one, then such a diagram would describe the genealogical relationships between species with a single, ancestral species at its base The Tree of Life is a Work in Progress • Just as researching your family tree can help you understand who you are and where you came from, the tree of life helps biologists understand the relationships between organisms and the history of species How Should we name Branches on the Tree of Life? • The effort to name and classify organisms is called taxonomy • Any named group is called a taxon • Woese proposed a new taxonomic category called the domain • The 3 domains of life are the Bacteria, Archea and Eukarya • Biologists often use the term phylum, to refer to major lineages within each domain Each phylum is considered a major branch on the tree of life • • One thing that hasn't changed for centuries is the naming system of individuals Scientific (Species) naming • In 1735, Carolus Linnaeus created a two-part name unique to each type of organism: • The first part indicates the organisms genus; a genus is made up of a closely related group of species • For example; Linnaeus put humans in the genus Homo • The second term in the two part name identifies the organisms species • Linnaeus gave humans the species name sapiens • An organisms genus and species designation is called its scientific name • Scientific names are alway
More Less

Related notes for BIOL 1001

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.