About the Book
Today’s plants are descended from simple algaes that first emerged more than 500 million years ago, and now there are around 400,000 species. The huge diversity of forms that that these plants take is staggering. From towering redwoods, to diminutive mosses; from plants that developed stinging hairs and poisons, to those that require fire to germinate tor ocean currents to dsitribute their seeds.
But how have we arrived at this mind-blowing variety in the plant kingdom? How Plants Work seeks to answer this intriguing question, drawing from a wide range of examples—from the everyday leaf to the most bizarre flowers.
Table of Contents:
Foreword by Professor Sir Peter Crane
Chapter 1: An Introduction To Plant Morphology
An extended introduction explains the basics of the field of plant morphology—the study of plant structures and their functions—and introduces the evolutionary context, from examples drawn from the fossil record, to the interrelation of plant form, function, and the habitat in which a species has evolved. It will also examine species diversity, convergent and parallel evolution, and the key influence of predation on plant form. Ethnobotany—the way humans have found uses for different plants—will also be explained, before the main chapters examining specific plant structures begin.
Chapter 2: Roots
This chapter examines roots and their roles in anchoring the plant, finding nutrients and water. It goes on to show how the roots of some plants serve as underground storage organs for energy and water while others are important in vegetative reproduction.
• The purpose of roots
• Mycorrhiza (root/soil fungi interactions)
• How deep? Surface rooting and deep rooting—what lies beneath? How the root systems of trees balance the aerial mass of the tree.
• Roots as underground storage - water and food reserves (examples of desert plants where most of the plant is underground)
• Contractile roots.
• Roots of climbing plants (such as ivy)
• Aerial roots and specialized roots of epiphytic orchids
• Pneumatophores – “breathing” roots of mangroves and swamp trees.
• Parasitic roots
• Roots and vegetative reproduction
• Buttress and stilt roots (tropical trees mostly)
• Root nodules (legumes and nitrogen-fixation)
Chapter 3: Stems & Trunks
This chapter examines stems and trunks of herbaceous and woody plants including branching architecture, primary and secondary growth (such as woody tissue).
• Types of bark—smooth, furrowed, fissured, corky, flaky
• Different types of wood
• Photosynthetic stems and bark
• Physical constraints on the height of trees
• Lianas, climbers, hangers on, and stranglers
• Shoots and buds (twisting, seeking light/dark, rough, smooth, spiny, thorny, forms of attachment in the case of climbers or scramblers, modified shoots)
• Annual growth rings – and what they can tell us
• Saps and resins
Chapter 4: Leaves
This chapter examines the enormous diversity of leaf shapes, sizes, arrangements, and forms, with stunning examples taken from a broad variety of plants from around the world.
• How leaves evolved
• The purpose of leaves
• Leaf anatomy and leaf arrangements
• An introduction to leaf form
• Evergreen vs. deciduous
• Leaf plasiticity (varying leaf forms within the same plant/populations – including examples of plants with different immature and mature foliage)
• Simple leaves
• Compound leaves
• Aromatic leaves
• Drip tips and other waterproofing mechanisms
• Leaf mimicry (deadnettles, mistletoe)
• Leaves adapted to protect against herbivory (spiny leaves, toxins)
• Leaves adapted for drought (cacti, succulents, Mediterranean plants)
• Leaves adapted for the capture of insects (pitcher plants, venus fly trap)
Chapter 5: Reproduction & Life Cycles
This chapter focuses on sexual reproduction in plants, how the male and female gametes are produced, how fertilization occurs. Plant life cycles and the alternation of generations.
• Life cycles and reproduction in cryptogamic plants which lack seeds: bryophytes (mosses and related plants) and peteridophytes (ferns and fern allies).
• Male and female gametes of plants
• Fertilization in plants (from free-swimming motile male gametes to pollen grains enclosing the male gametes)
• The origins of seeds (structures that develop from the fertilized ovules)
• Introducing the main kinds of organs involved from cones to flowers (subject of the next chapter) and seeds and fruits (subject of chapter 6).
Chapter 6: Cones & Flowers
This chapter provides an exploration of cone and flower (reproductive structures of seed plants) diversity, basic structures, and diversity of form. It examines the different pollination mechanisms that plants have adapted and how they dictate the form of the flower.
• The evolution of cones and flowers
• The purpose of flowers and cones (pollination, protection of the developing embryo and seed)
• Cone and flower anatomy (symmetry, asymmetry, flower arrangements—e.g. corymbs and other inflorescences)
• An introduction to the variety of flower form
• Pollination by wind, animals and water
• Floral attractants for pollinators (nectar, scent, mimicry)
• Seasonality
• Cauliflory (where flowers appear on trunks), underground flowers, etc
Chapter 7: Seeds & Fruits
An explanation of how fruits develop from flowers and the purpose that their form serves in the distribution of the all-important seeds. Often overlooked, the diversity of seeds is huge, from the enormous coco-de-mer to the tiny dust-like seeds of orchids.
• The roles of seeds and fruits in survival and dispersal of plants
• The longevity of seeds (some can germinate after thousands of years)
• Anatomy and development of seeds (the distinction between seeds and fruits)
• Anatomy and development of fruits
• Diversity of seeds and fruits (dry and succulent fruits, dehiscent, schizocarpic and indehiscent fruits)
• Dispersal of seeds and fruits – by wind, water and animals
• Germination and the factors (fire, moisture, etc) which can trigger it
• Parthenocarpic fruit (fruit without seeds, e.g. banana)
Chapter 8: The Influence Of Man
Many plant forms we see today are modifications or exaggerations of natural forms, selected or bred by humans for our own benefit. In these, we see a subtle shift in the ‘meaning’ of plant forms—from an expression of their responses to environmental challenges to a form that is primarily beneficial to humans. The domestication of maize provides one example, the selection of seedless fruits (which cannot reproduce naturally) another.
All of the topics tackled in this section will compare wild and cultivated forms, with a discussion of how their new forms have been developed, and the possible future implications. Finally the chapter will explore human impacts of the diversity of wild plant species and the efforts underway to conserve and protect them.
• Early human interactions with plant diversity
(ethnobotany, medicinal, edible and other useful plants)
• Plant domestication and the rise of agriculture – a focus on cereal crops compared to grasses.
• Food crops
• Fibres
• Medicines derived from plants
• Cut flowers and garden varieties developed in horticulture (double flowers, weeping varieties, etc)
• Human impacts on plant diversity: the threats to plants in the wild and the efforts to protect them (from seed banks to botanic gardens and from protected areas to ecological restoration
Glossary of terms
Visual dictionary of plant structures
References and further reading
Index
About the Author :
Stephen Blackmore CBE FRSE FRSB FLS is a British botanist, who was educated at St. George’s School, Hong Kong and the University of Reading where he completed his PhD. He then worked at the Royal Society of London’s Research Station on Aldabra Atoll in the Indian Ocean before being appointed Lecturer in Biology and Head of the National Herbarium and Botanic Garden at the University of Malawi. In 1980, he was appointed Head of Palynology at Natural History Museum in London and from 1990 to 1999 served there as Keeper of Botany. He was the 15th Regius Keeper of the Royal Botanic Garden Edinburgh from 1999 until 20 December 2013, and was appointed Her Majesty’s Botanist in Scotland in 2010. Stephen has contributed to a number of successful books including the Pengion Dictionary of Botany, A Natural History of Belize, and Plants of China.
