Organizing the living world

Organizing the - O rganizing the living world 1 Adaptive radiation-occurs when a single lineage produces many descendant species that live in a

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Organizing the living world: 1. Adaptive radiation: -occurs when a single lineage produces many descendant species that live in a wide diversity of habitats and find food in a variety of ways. (Star polytomy). -a cluster of closely related species that are each adaptively specialized to a specific habitat or food source -Evolution of a number of divergent species from a common ancestor each species becoming adapted to occupy a different ecological niche. 2. Advanced characters: - Changed from the original condition. Derived from the original to better suit the present. Fairly subjective, source of conflict. Classical division between North America and Europe. Seen as “better than something” -more recent evolutionary origin -Primitive characters 3. Analogous: -Structures that are similar in function but not in structure and developmental and evolutionary origin. Ex: insect and bird wings. -homoplasious (homoplasies), phenotypic similarities that evolved independently in different lineages 4. Apomorphy: -a novel character evolved from a preexisting character -The original character and the derived character form a homologous pair termed an evolutionary transformation series 5. Artificial taxonomy: - Greek philosophers wrote down info contained in the folk taxonomies compiling lists of living things. Plato and his students Aristotle(animals) and Theophrastus(plants). -Texts became reference tool used around the world -Detailed descriptions rather than names 6. Character convergence: - in evolution the condition in which 2 newly evolved species interact in such a way that one or both converges in one or more traits towards the other. -They are structurally similar even though they appeared independently in taxa that didn’t have an immediate common ancestor. Type of homoplasy
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
7. Character reversal: -happens when a character that is unique to a taxon group reverts to a more ancestral level in a taxon within this group. 8. Cladistics: -method of classification of living organisms that makes use of lines of descent only, rather than phenotypic similarities, to deduce evolutionary relationships and which groups organisms strictly on the relative recentcy of common ancestry. -only permit taxa in which all the members share a common ancestor who is a
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/09/2011 for the course BIO 1130 taught by Professor Fenwick during the Spring '08 term at University of Ottawa.

Page1 / 6

Organizing the - O rganizing the living world 1 Adaptive radiation-occurs when a single lineage produces many descendant species that live in a

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online