III Plant Diversity B Tracheophyte Origins 1 The

III. Plant Diversity B. Tracheophyte Origins 1. The Rhyniophyta -vascular system of phloem and xylem

III. Plant Diversity B. Tracheophyte Origins 1. The Rhyniophyta Silurian – 440 mya -vascular system of phloem and xylem -“tracheids” in sporophytes -- water and nutrient distribution

Gymnosperms Angiosperms

III. Plant Diversity B. Tracheophyte Origins 1. The Rhyniophyta -vascular system of phloem and xylem -“tracheids” in sporophytes -- water and nutrient distribution -- lignin and support

III. Plant Diversity B. Tracheophyte Origins 4. Life History: simple (primitive) - Homospory

III. Plant Diversity C. Non-seed Tracheophytes 1. Lycophytes (Club Mosses)

III. Plant Diversity C. Non-seed Tracheophytes 1. Lycophytes - (Club Mosses) - ancient; dominated first “forests” 300 -350 mya Lepidodendron - 45 m -Carboniferous

III. Plant Diversity C. Non-seed Tracheophytes 1. Lycophytes - (Club Mosses) - ancient; dominated first “forests” 300 -350 mya - simple leaves

III. Plant Diversity C. Non-seed Tracheophytes 1. Lycophytes - (Club Mosses) - ancient; dominated first “forests” 300 -350 mya - simple leaves - Dominant Sporophyte (with stobili)

III. Plant Diversity C. Non-seed Tracheophytes 1. Lycophytes - (Club Mosses)

III. Plant Diversity C. Non-seed Tracheophytes 1. Ferns “and their allies”

III. Plant Diversity C. Non-seed Tracheophytes 1. Ferns “and their allies” - true complex leaves

III. Plant Diversity C. Non-seed Tracheophytes 1. Ferns “and their allies” - true complex leaves - true roots

III. Plant Diversity C. Non-seed Tracheophytes 2. Ferns “and their allies” - true complex leaves - true roots - also ancient; appearing 350 mya - dominant sporophyte; reduced gametophyte

Fern Life Cycle:

III. Plant Diversity D. Seed Tracheophytes - heterospory

III. Plant Diversity D. Seed Tracheophytes - heterospory - seeds: lipid-rich endosperm packaged with the zygote

III. Plant Diversity D. Seed Tracheophytes 1. General Characteristics - heterospory - seeds: lipid-rich endosperm packaged with the zygote -pollen: - no more swimming sperm!!

III. Plant Diversity D. Seed Tracheophytes 2. Gymnosperms – “naked seed” a. Evolutionary History - dominated during Permian (280 mya) and through Mesozoic, and still dominate in dry env. Today (high latitudes, sandy soils)

III. Plant Diversity D. Seed Tracheophytes 2. Gymnosperms – “naked seed” a. Evolutionary History - dominated during Permian (280 mya) and through Mesozoic, and still dominate in dry env. Today (high latitudes, sandy soils) b. Diversity - cycads - ginko - Gnetales - conifers

III. Plant Diversity D. Seed Tracheophytes

c. Gymnosperm Life Cycle

III. Plant Diversity D. Seed Tracheophytes 3. Angiosperms – “flowering plants” - double fertilization - triploid endosperm

III. Plant Diversity D. Seed Tracheophytes 3. Angiosperms - double fertilization - triploid endosperm - fruits - flowers Both serve to bribe animals to disperse either Pollen or seeds NON-RANDOMLY. More likely to end up in a similar habitat.

III. Plant Diversity D. Seed Tracheophytes 3. Angiosperms - Angiosperm History

III. Plant Diversity D. Seed Tracheophytes 3. Angiosperms - Angiosperm History - Diversity - evolutionary trends: primitive derived insect pollinated wind pollinated terrestrial aquatic “woody” herbaceous