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Home , Abelia, Adoxaceae, Centranthus ruber, Honeysuckle, Lonicera ciliosa, Monarda didyma

BIOL 317: Identification and Classification Summer 2015 - Notes

Week 7 – Tuesday  Core  comprises two large clades, the campanulids and the lamiids  commonly shared traits: • 5-merous • gamopetalous corolla • 5 in a single whorl, alternate with lobes • epipetalous stamens • 2 fused carpels

 Campanulids  typically have inferior ovary

 another important family is (elderberry, )

( family)  42 genera, 890 spp.  distributed widely, but especially diverse in northern temperate zone  herbaceous or woody ( or )  - simple or compound; opposite  • zygomorphic, some weakly so • 5, fused • 5, fused . often bilabiate, with 2 upper petal lobes and 3 lower petal lobes (notable exception is Lonicera [honeysuckle] which has 4 upper petal lobes and 1 lower petal lobe) • stamens 4 or 5, epipetalous • pistil compound (2-5 carpels); ovary inferior . usually 1 ovule/carpel; in some , only 1 carpel matures • : capsule, achene, , or drupe  Older circumscriptions of Caprifoliaceae were paraphyletic with respect to Adoxaceae, Dipsacaceae, and , families with mostly herbaceous members. In order to make monophyletic families, and Viburnum were transferred to Adoxaceae, which all have actinomorphic flowers. Dipsacaceae and Valerianaceae were sunk into Caprifoliaceae in the classification followed here. Other phylogenetic classifications maintain Dipsacaceae and Valerianaceae, define Caprifoliaceae as a narrower clade, and erect new families Linnaeaceae, Diervillaceae, etc.  includes PNW shrubs and wildflowers ( - orange honeysuckle, albus - snowberry, borealis - twinflower, sitchensis - Sitka , etc.), weeds (Dipsacus fullonum - teasel, etc.), and ornamentals (Weigela sp., sp., - Japanese honeysuckle, ruber - red valerian, columbaria - pincushion flower, etc.)

 another important family is Araliaceae (ginseng, English-ivy)

(carrot family)  484 genera, 3780 spp.  distributed worldwide, but especially diverse in northern temperate zone  herbaceous  leaves - often compound, some simple; alternate; sheathing base  often aromatic - possess ethereal oils, terpenoids, and other volatile chemicals used for herbivore defense  - umbel (pedicels originate from single point and flowers produced at about the same level); many with compound umbels  flowers • actinomorphic or zygomorphic • sepals 5 • petals 5, free - secondary loss of fusion • stamens 5 • pistil compound (2 carpels); ovary inferior . 1 ovule/carpel . stylopodium - swollen style base secretes • fruit: schizocarp  includes PNW wildflowers (Lomatium spp. - desert-parsley, spp. - sanicle, Heracleum maximum - cow-parsnip, Angelica spp., etc.), weeds (Conium maculatum - poison-hemlock, etc.), food crops, herbs, and spices (Daucus carota - carrot, Pastinaca sativa - parsnip, Apium graveolens - celery, Foeniculum vulgare - fennel, Petroselinum crispum - parsley, Coriandrum sativum - cilantro, coriander, Pimpinella anisum - anise, Cuminum cyminum - cumin, Carum carvi - caraway, etc.), and ornamentals (Eryngium amethistium - sea holly, etc.)

 Asterales  often have secondary pollen presentation (also called plunger or brush pollination, or a pollen pump) • Anthers of stamens form tube through which style and stigma grow. Pollen is deposited on outside of immature stigma lobes, where it is presented to . Later, the stigma lobes mature and open to expose the inner receptive surface.  Campanulaceae (bellflower family)  84 genera, 2380 spp.  distributed worldwide  most herbaceous, some woody (shrubs)  leaves - simple; alternate  milky latex  flowers • actinomorphic (subfamily Campanuloideae) or zygomorphic (subfamily Lobelioideae) • sepals 5, fused • petals 5, fused . bell- or tube-shaped (subfamily Campanuloideae) . 2- or 1-lipped (subfamily Lobelioideae) • stamens 5 . secondary pollen presentation - anthers fused or held together to form tube around pistil • pistil compound (2-5 carpels); ovary inferior • fruit: capsule or berry  includes PNW wildflowers (Campanula spp. - bellflower, Downingia spp., etc.) and ornamentals (Campanula spp., Lobelia spp., etc.)

 Asteraceae/Compositae (sunflower family)  1620 genera, 23600 spp. - among the two largest families of angiosperms  distributed worldwide  herbaceous or woody (shrubs or trees)  leaves - usually simple, but can be highly dissected; variously arranged  inflorescence - head (capitulum) - sessile flowers densely clustered • subtended by whorl (involucre) of (phyllaries) • discoid head - have only disk florets • ligulate head - have only ligulate florets • radiate head - have ray florets at margin, disk florets in center  flowers • actinomorphic (disk floret) or zygomorphic (ray or ligulate floret) • flowers sometimes individually subtended by bracts on the receptacle (chaff) • sepals none, or 2-many . if present, then highly modified into scales or bristles (pappus) • petals 5, fused . tube-shaped (disk floret) . form ligule - expanded single lobe (ray or ligulate floret) • stamens 5, epipetalous . secondary pollen presentation - anthers fused together to form tube around pistil • pistil compound (2 carpels); ovary inferior . 1 ovule/carpel, but only 1 carpel matures • fruit: achene (cypsela)  includes PNW shrubs and wildflowers ( tridentata - big sagebrush, Cirsium spp. - thistle, Balsamorhiza sagitata - arrowleaf balsamroot, Arnica spp., Erigeron spp. - fleabane, etc.), weeds ( officinale - dandelion, Centaurea spp. - knapweed, etc.), food crops (Lactuca sativa - lettuce, Cynara cardunculus - artichoke, Helianthus annuus - sunflower), and ornamentals (Chrysanthemum spp., Zinnia spp., Tagetes spp. - marigold, etc.)

 Plant Speciation  Species concepts - what is a species? • are species real units that exist in nature, or are they human constructs used to simplify, organize, and understand nature? • what concepts are used to define and delimit species? . typological - a perfect form exists for each species, and any variation is the result of unimportant environmental imperfections - prevailing concept from ancient Greeks (Plato, Aristotle) to Linnaeus . morphological - variation in morphology is important and should be measured, and species boundaries are defined by gaps or discontinuities in morphology - rose in prominence after Darwin . biological - species boundaries are defined by reproductive isolation - advocated by Ernst Mayr (1940's) . mate-recognition - species defined by mating specificity and share common mating/fertilization system . phylogenetic - species are monophyletic groups that share derived traits (synapomorphies) • Most concepts revolve around the idea that species are unique evolutionary lineages, but differ in how lineages are determined to be divergent enough from others to warrant being called a new species. Given the diversity of life- histories and evolutionary histories found across the tree of life, it is unlikely that any one species concept will be suitable and applicable to all organisms.

Week 7 – Thursday  Plant Speciation (cont.)  Speciation - how do new species form? • new species are derived from previously existing species • new species begin to form when a population becomes isolated from its parent population, so that the exchange of genetic material (gene flow) ceases • Allopatry - geographic separation . most speciation events are believed to have begun when populations became geographically isolated . while geographically isolated, populations may accumulate genetic differences due to:  selection - different environments in different areas may select for different beneficial mutations in the different populations  drift - different mutations may become prevalent in different populations by random chance . if populations later meet, they may:  hybridize - genetic differences do not affect the ability of populations to successfully mate, and the populations merge and remain a single species  be genetically incompatible - genetic differences cause hybrid offspring to be inviable, infertile, or unfit - in this case, developing mating barriers becomes adaptive and may be selected for (reinforcement), so individuals do not waste resources on mating events that produce unfit offspring  have mating barriers - genetic differences result in morphological/developmental/behavioral differences that prevent individuals from different populations from mating . mating barriers  temporal - differences in timing of reproduction, during the course of the day (diurnal) or year (seasonal)  habitat - differences in habitat preference may lead to fine-scale geographic separation  floral - differences in morphology of the flower - may attract different pollinators - structural differences may result in interactions with the in different ways, e.g. deposit pollen on different areas of the pollinator's body • Other modes of speciation (especially common in ) . Hybridization - hybrid offspring may persist but be unable to mate with either parent species, thus forming a new species  hybrid offspring are often sterile due to chromosomal incompatibilities between parental genomes, but hybrid plants may persist by asexual reproduction

. Polyploidization - increase in the number of sets of chromosomes, e.g. from diploid (2 sets) to tetraploid (4 sets)  may result in instantaneous speciation since individuals of different ploidy levels usually cannot successfully interbreed  polyploidization in hybrids often results in regained fertility, so hybrids may reproduce sexually

 Lamiids

 typically have bilabiate corolla (2-lobed) and didynamous stamens (2 long + 2 short stamens)  other important families include Oleaceae (olive, lilac) and Verbenaceae (verbena)

 "Scrophulariaceae" (snapdragon family)  we are using the older circumscription, which gives a non-monophyletic group (often considered polyphyletic), which is defined by a general Lamiales floral morphology (bilabiate corolla, didynamous stamens) and lack of any obvious derived traits • more recent phylogenetic classifications divide the group into about six families, including : . Scrophulariaceae sensu stricto - flowers usually actinomorphic or weakly zygomorphic; most diverse in southern hemisphere; includes Scrophularia spp. (figwort) and Verbascum spp. (mullein) . Plantaginaceae - includes most well-known members of the group: Antirrhinum spp. (snapdragon), Digitalis spp. (foxglove), Penstemon spp. (beardtongue), etc. . Phrymaceae - small family contains plants with sensitive stigma; includes Mimulus spp. (monkeyflowers) . Orobanchaceae - holoparasites and hemiparasites; includes Castilleja spp. (indian paintbrush), Pedicularis spp. (lousewort), etc.  269 genera, 5100 spp.  distributed widely, but especially diverse in northern temperate zone  most herbaceous, some woody at base (sub-shrubs)  leaves - simple; alternate or opposite  flowers • usually zygomorphic • sepals usually 5, some 4; fused • petals usually 5, some 4; fused . often bilabiate, with 2 upper petal lobes and 3 lower petal lobes • stamens usually 4, some 2; epipetalous . usually didynamous arrangement . some have 5th that is sterile (staminode) • pistil compound (2 carpels); ovary superior . many ovules/carpel • fruit: usually capsule  includes PNW wildflowers (Penstemon spp. - beardtongue, Mimulus spp. - monkeyflower, Castilleja spp. - indian paintbrush, etc.), weeds (Verbascum spp. - mullein, etc.) and ornamentals (Antirrhinum majus - snapdragon, Digitalis purpurea - foxglove, etc.)

/Labiatae (mint family)  236 genera, 7173 spp.  distributed worldwide  herbaceous or woody (shrubs)  leaves - usually simple; opposite and decussate (adjacent pairs of leaves are at 90 degrees to each other)  stems often square in cross-section  often aromatic - possess ethereal oils, terpenoids, and other volatile chemicals used for herbivore defense  inflorescence - cymes produced in lateral axes (as axillary ); often form verticels (whorls of flowers) at nodes  flowers • zygomorphic • sepals 5, fused • petals 5, fused . often bilabiate, with 2 upper petal lobes and 3 lower petal lobes • stamens usually 4, some 2; epipetalous . usually didynamous arrangement • pistil compound (2 carpels); ovary superior . 2 ovules/carpel - divided by false septum to form 4-lobed ovary • fruit: schizocarp, forming 4 nutlets  includes PNW wildflowers (Scutellaria spp. - skullcap, dorii - gray-ball sage, odoratissima - mountain monardella, etc.), herbs (Salvia officinalis - sage, Rosmarinus officinalis - rosemary, Thymus vulgaris - thyme, Origanum vulgare - oregano, Ocimum basilicum - basil, Mentha spp. - mint, Lavandula spp. - lavender, etc.), and ornamentals ( didyma - scarlet beebalm, Salvia splendens - scarlet sage, Plectranthus scutellarioides - coleus, etc.)

 Parasitic plants  Organisms have two modes of obtaining energy • autotrophy - produce own food • heterotrophy - obtain food from other organisms  Autotrophic plants use light energy to convert carbon dioxide and water to sugars and oxygen via photosynthesis • adaptations for photosynthesis: . broad thin leaves for intercepting sunlight . system (stems, petioles) for positioning leaves to intercept sunlight  Parasitic plants - obtain energy from host at host's expense • Parasite may obtain energy from: . fungi - mycotrophy; found in Orchidaceae, Ericaceae, etc. . plants  roots - parasite connects via host's roots; found in "Scrophulariaceae" (Orobanchaceae) , etc.  branches - parasite connects via host's branches; found in Santalaceae (mistletoe), Convolvulaceae (dodder), etc. • Parasites vary in their ability to photosynthesize . holoparasite - unable to photosynthesize; all energy derived from host . hemiparasite - retains ability to photosynthesize • Parasitic reduction syndrome - suite of traits commonly associated with parasitism, which evolved independently in different groups . reduced leaves . reduced overall size . reduced roots . haustoria - specialized swellings on roots penetrate host tissue . loss of chlorophyll . loss of genes for photosynthesis . higher substitution rate for genetic mutations

 Plant biogeography  Study of the distribution of plants • patterns in where vegetation types and lineages of plants are found • causes of distribution patterns  Ecological (contemporary) factors • Climate . precipitation . temperature • to be continued...