Plant Structure & Function (BIOEB204) — Introductory Lecture

Instructor & Personal Background

  • Lecturer: Mike Clearwater
    • Email supplied on first slide (not reproduced here)
    • Office: D-103
  • Motivation: “I love trees—big woody plants fascinate me.”
  • Research history & photo anecdote
    • PhD on seedling growth in tropical rain-forest, Borneo.
    • Climbed a 60 m60\ \text{m} radio mast to mount a weather station and take hemispherical photographs for canopy-cover analysis.
    • Wouldn’t attempt that climb today—“a bit crazy.”

A Striking Example Plant: Blue Selaginella

  • Iridescent, structural blue (not pigment; analogous to peacock feathers).
  • Hue disappears when leaf is tilted—proof the color derives from cuticle micro-structure.
  • Possible adaptation to deep-shade light environments.

Lecture 1 Agenda & Learning Outcomes (LOs)

  • Orientation: Why the course exists, structure, outcomes, logistics.
  • Introduction to the concept of plant form and function.
  • Specific LOs shown on slide (readable later on Moodle)—will be provided every lecture.

Why Are We Here? ‑ Student Engagement

  • Mike will open a Q&A forum on Moodle with the thread “Why we are here.”
    • Share whether you’re taking the paper as a requirement or out of genuine plant interest.
    • Thread aims to build community & surface motivations.
  • Example of rare motivation driver
    • Tiny threatened New-Zealand orchid (flowers 2$–$3\ \text{mm} wide).
    • Declining because collectors remove plants once location becomes public.

Real-World Justifications for Plant Biology

  • Biosecurity threat: Myrtle rust (rust fungus)
    • Arrived 2017 after wind dispersal across Tasman.
    • Targets Myrtaceae—including pōhutukawa, mānuka, kānuka; ecological stakes are huge.
  • Land-use & erosion (Cyclone Gabrielle)
    • Forestry slash & sediment damage lowlands; long-running East-Cape debate:
    • Steep erodible slopes ➜ Harvested exotics?
    • Or permanent indigenous re-forestation?
  • Predator control linked to mast-seeding
    • Beech & podocarp mass flower/fruit irregularly; climate cue identified by plant scientists.
    • DOC now times 10801080 drops to coincide with projected seed booms → mitigates rat/mustelid explosions.
  • Climate-emergency response
    • Forestry / carbon farms central to NZ policy.
    • Big unanswered questions: native vs exotic forests, cost, long-term viability.
  • Food production & sustainability
    • All food traces back to plants.
    • Life-cycle analyses show land-use & GHG gradient:
      \text{Plant foods} < \text{Eggs} < \text{Poultry/Fish} < \text{Dairy} < \text{Beef/Lamb}
    • Diet choice = planetary impact lever.

Course Structure (Three Conceptual Blocks)

  1. Plant Structure & Function
    • Anatomy, transport, photosynthesis, mineral nutrition.
  2. NZ Flora & Vegetation
    • Emphasis on identification of native trees (list of 30 species supplied).
  3. Plant Diversity Survey
    • Bryophytes → Ferns → Gymnosperms → Eudicots
    • Includes economically important species (e.g.
      Pinus radiata).
  • Continuous thread: learn to recognise native & key economic plants.

Learning Outcomes (Condensed)

  • Describe & diagram plant anatomy, water transport, photosynthesis.
  • Relate NZ vegetation patterns to environmental drivers.
  • Accurately ID 30 common natives & discuss traits.
  • Produce scientific writing (report) and visual communication (poster).

Delivery & Weekly Rhythm

  • Recorded mini-lectures: 3–4 per week (watch before workshop).
  • Weekly workshop (Mon 09:00–11:00):
    • Active, group-based tasks linked to video content.
    • Bring laptop/tablet for online quizzes/worksheets.
  • Laboratories: Practical work incl. microscopy, dissections, herbarium material.
  • Field trip: Mid-semester Saturday; details in course outline.

Assessment Breakdown (No Final Exam!)

  • Workshops: 10 (marked)×5%=50%10 \text{ (marked)}\times5\% = 50\% (top 10 of ~12 count).
  • Two Plant-ID tests: 25%25\% total.
  • Lab report (first 3 labs): ?%?\% (exact % listed on Moodle slide).
  • Poster assignment (second half, linked to biodiversity block).
  • Missed workshop → still submit online, or apply for special consideration.

Feedback & Class Representation

  • End-of-semester course appraisal + informal feedback anytime.
  • Seeking one Class Rep
    • Email Mike ➜ fill School-of-Science Google form (QR/link forthcoming).

Conceptual Foundation: Form vs Function

  • “Function” ≈ Plant physiology—how it works.
  • Evolution suggests form often tracks function, yet…
  • Example question: Why do many tropical plants have drip tips?
    • Hypotheses: faster leaf drying ➜ fewer epiphylls; reduced erosion via drop size, etc.
    • Empirical support still weak.

The Spandrel Analogy & Adaptationist Caution

  • Spandrel: architectural space created when a dome sits on columns (painted famously by Michelangelo).
  • Stephen J. Gould & Lewontin (1979) essay “The Spandrels of San Marco…”
    • Warned biologists not to declare every trait an adaptation (“Panglossian paradigm”).
    • Some features are by-products or developmental constraints, not direct adaptive targets.
  • Application to plants
    • Don’t assume every structural oddity (e.g.
      drip tips, domatia) evolved for its putative function.
    • Requires careful testing & historical perspective.

Another Mystery Structure: Leaf Domatia

  • Tiny pockets/caves on undersides of some leaves (notably Coprosma in NZ).
  • Useful for species ID in this course.
  • Hypothesis: provide housing for predatory mites that clean leaf surface of fungi/arthropods (see reference on slide).
  • Again illustrates form-function debates.

Action Items Before Week 1 Workshop

  • Log into Moodle
    • Read full course outline (schedule, labs, field trip).
    • Post in “Why we are here” forum.
  • Watch remaining three mini-lectures for Week 1.
  • Monday 09:00: attend Workshop 1 with a charged device & readiness to collaborate.
  • Begin thinking about plant forms that intrigue you—bring questions!