Dendrology FOR 320 Spring Semester 2013

Transcription

1 Dendrology FOR 320 Spring Semester 2013 Week 1; Wednesday Introductions - Instructor, TAs, Peer TAs Announcements: Handouts - Syllabus - go over this with class - Web Site - Expectations - lecture, lab, exams, quizzes, lab exams, makeups, etc. Lab times explain old format, switch to new format, time schedule mix-up Labs will be 1 hour and 20 min, not 2 hours! 1 st lab section: MW 1:30 2:50 (NOT 3:20) 2 nd lab section: MW 3:30 4:50 (NOT 5:20) Books: Optional: Farrar, JL. Trees of the Northern United States and Canada. Blackwell Publishing. Hardin et al. Textbook of Dendrology. 9 th edition. (ca. $80 used) Required materials: 10X hand lens (ca. $7), lab notebook (3-ring binder) for drawings and notes. Field trips Friday campus walks required (regular lecture time rain or shine!) Clarkia fossils (Sat. April 16) optional Lewiston valley (Sat. April 30) optional Field trip waivers, please fill out front and sign. Need before we can go on any campus walks first one next Friday. So, get to me ASAP. Labs Start NEXT WEEK! - Lab exercises will be posted as pdfs on webpage by Sunday before the week s lab. Please print these out and bring with you to lab WE WILL NOT HAVE THESE AVAILABLE IN LB SO IT IS YOUR RESPONSIBILITY TO PRINT AND BRING WITH YOU!!! Keep in 3-ring binder and biuild as a resource for studying etc. 1

2 What is Dendrology? Dendrology literal translation study of trees this is a pretty broad definition and could encompass pretty much any botanical discipline! more specific dendrology covers the systematics (classification and phylogenetic relationships), morphology, ecology, geography, and natural history of woody plants. In other UI forestry classes you will focus on ecological processes, silviculture, production, etc., but this is the only class in CNR at UI that has evolutionary patterns as a central organizing principle. With a solid understanding of the principles and philosophies of evolution and classification (i.e., systematics) we can learn what types of characters are good characters useful in determining relationships and establishing classifications and what types of characters are misleading not the result of common ancestry, but rather convergent etc. so you are better able to make predictions and apply knowledge. Today s Lecture: Nomenclature and Classification What is Classification? Classification - the sorting of things into groups and the assigning of names to those groups. Classification (for biology) The grouping of organisms into categories based on shared characteristics or traits. Examples: Libraries many cultures have developed classification systems of plants, often based in how plants were used (food, fiber, medicine). o Classification in action at your local Safeway Similar to many indigenous systems of classification which are often organized by utility. Why is this important? Dealing with large amounts of information Essential to our understanding and communication about the natural world Power of prediction To make sense of comparative studies (e.g., genetics, crop improvement, ecology, evolution, diversity). Prevents comparing apples and oranges! In short, classification is the way we communicate about biological diversity Scientific system of classification Comes down to us from the Greeks, and is based on morphological similarity. Today, scientists use: 1. Visible morphology 2. Anatomy internal or microscopic structures 3. Chemicals presence/absence of proteins, pigments, and toxins 4. Genetics chromosome #, DNA similarity 2

3 Week 1; Friday Anouncements: Field trip waivers, please fill out front and sign. Need before we can go on any campus walks first one next Friday. So, get to me ASAP. Reminder - notes will be posted at the end of each week. Print lab materials Ended last time talking about classification - in short, classification is the way we communicate about biological diversity - and what types of data scientists use today to assess similarities among organisms. Scientific system of classification Comes down to us from the Greeks, and is based on morphological similarity. Today, scientists use: 5. Visible morphology 6. Anatomy internal or microscopic structures 7. Chemicals presence/absence of proteins, pigments, and toxins 8. Genetics chromosome #, DNA similarity You don t need to be a scientist or have formal training to recognize similarities among plants. We have come up with common names to categorize many plants around us. For example, lily refers to several things we have an image of in our mind. This is a classification system, and it works pretty well. However, the problem with common names is that there are no rules for usage, and this leads to confusion. One kind of plant will have different names in different places, or there will be many kinds of plants with the same common name. Example: Cedar Cedar here, E. US, and Europe are three entirely different plants! In fact, a dictionary of plant names lists 25 different taxa under the name Cedar. Many attempts to avoid such pitfalls. Originally, a formal plant name could include a dozen Latin adjectives in an effort to make the name apply to just one plant and no other. Solanum caule inermi herbaceo foliis pinnatis incises Solanum with the smooth stem that is herbaceous and has incised pinnate leaves Solanum lycopersicum Linnaeus system Species Plantarum (1753) Carol von Linne (Swedish botanist) came up with a simple scheme that immediately became very popular. He used just two words to describe the organism. binomial nomenclature - Each species has a two word Latin name consisting of its genus and species names. These words are always underlined or italicized when written. Example: Thuja plicata western red cedar to us in the PNW 3

4 hierarchical system - groups nested in larger groups OVERHEADS For example: western red cedar Kingdom Phylum (Division) Class Order Family Genus Species Plantae Coniferophyta Coniferopsida Coniferales Cupressaceae Thuja Thuja plicata Use this mnemonic to remember: King Phillip Came Over From Great Spain Another example: Big Leaf Maple Kingdom Phylum (Division) Class Subclass Order Family Genus Species Plantae Magnoliophyta Magnoliopsida Rosidae Sapindales Aceraceae Acer Acer macropyllum This system of nested, hierarchical levels (smaller groups nested in larger groups) gives us flexibility to 1) expand our classification system to include new discoveries without starting from scratch, and the 2) ability to organize large numbers of things. Emphasize species name is made up of Genus and specific epithet BINOMIAL Linnaeus called his system the Sexual System, because he used the presence or absence and number of sexual parts as the basis for classification. OVERHEAD Linnaeus classified all life including plants but his classification was inherently artificial Artificial classification - with no regard for evolutionary relationships (e.g., any classification of things other than living things would have to be artificial). However, evolutionary relationships make biological classification inherently different than other classifications (i.e., the tree of life ) Natural, or Phylogenetic, classification - reflecting evolutionary relationships. Darwin (1859 On the Origin of Species) was the first to suggest that any classification of life should be genealogical and would naturally be hierarchical; now we call this phylogenetic OVERHEADS 4

5 Today we call this phylogeny, and phylogenetic relationships shape our classifications. Much of the Linnaean system is still intact, because the characters he used are good indicators of evolutionary relationships Taxonomists over time have placed more and more emphasis on developing natural classification systems that reflect the phylogeny of a group of taxa. As a result, our classifications are dynamic Introduction to Phylogeny: Tree thinking OVERHEAD - Bonnett (1745) - great chain of being Darwin (1859) - On the Origin of Species -2 primary ideas that are central to evolutionary theory as presented by Darwin 1. the process of natural selection 2. that all species, despite the incredible diversity of life, are the result of decent with modification from a common ancestor (OVERHEAD) To communicate this idea, Darwin developed the metaphor of the tree of life OVERHEAD OVERHEAD from Ridley contrasting Evolution as a bush vs. ladder... This caught on - (OVERHEADS) - Haekel trees Today we call this PHYLOGENY and this has changed the way we think and communicate about biological diversity 5