Class Notes (836,587)
Canada (509,861)
Biology (2,256)
BIOL 359 (83)
Lecture 1

BIOL 359 Lecture 1: Phylogenetic

2 Pages
Unlock Document

BIOL 359
Kristen Muller

Phylogenetic: Study of ancestor descendant relationships Phylogeny: hypothesis, not final answer because things can change w/ new data of ancestor descendant relationships Phylogenetic Tree: to understand patterns of relationships Example: Domain of Life: SSurRNA (Small Subunit rRNA) data (all organisms have this gene, need to survive) • All life forms are related by common ancestry and descent • Phylogenies explain diversity seen in natural world o Can be based on morphological, physiological and/or molecular data o DNA sequence data typically used Phylogenetic Trees: • Rooted tree: time is implied on tree, back of tree is more in time (ancestor) (Figure A/B) on slide 5 o Polygamy/Comb: usually need more data to see relationship Phylogenetic Characters: • Characters bed to construct phylogenies • Can be any attribute of organism that can show relationships in history (shared ancestry) o Mammary glands in mammals • Molecular phylogenies usually look at nucleotide positions • Plesiomorphy: ancestral characteristics o Mammals and mammary gland (synapomorphy) apart from reptiles o Not informative on relationship, but it shows difference between organisms • Apomorphy: Character state different than ancestral state/derived state o Unique to particular species and all of its descendants, defining character for species/group o Example: Possession of feathers is unique to birds and defines them • Synapomorphy: derived character state (apomorphy) that’s shared by two or more taxa from common ancestor o Example: Mammary glands • Autapomorphy:Uniquely derived character state o distinct from ancestors • Monophyletic: All descendants of common ancestor (Clades) o Reptiles with inclusion of birds is considered monophyletic • Non-Monophyletic o Paraphyletic: includes some but not all descendants of common ancestor ▪ Reptiles group, when not including birds (Before discovery that they are related) o (Autapomorphy) birds were distinctly derived (highly derived) group from reptiles o Polyphyletic: grouping of taxa based on homoplasious characters ▪ Vultures in birds, new and old ▪ Doesn’t include most recent ancestor • Homoplasy: shared character that occurs due to independently evolved, not due to common ancestor (Same as analogy) o Warm blooded in some organisms are not due to common ancestor, but may be due to environment o Arose at different times (convergence) o Parallel: independent evolution of the same feat
More Less

Related notes for BIOL 359

Log In


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.