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Introduction to BotanyIntroduction to BotanyRead also: Banack et al. 2006. J Ethnopharmacology 106: 97-104.

I. Cycads Stories

I. Cycads StoriesA. Morphology

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©CR Hardy

2. Terminal cluster of

pinnate lvs

3. Unbranchedstem

1. Trees & shrubs


pinnate lvs

3. Unbranchedstem

1. Trees & shrubs

©CR Hardy


pinnate lvs

3. Unbranchedstem

1. Trees & shrubs

©CR Hardy

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Megasporophyll

Ovule (seed)

©CR Hardy

4. Gymnospermous

a. Seeds loosely clustered

b. or in strobilus

4. Gymnospermous

I. Cycads StoriesB. Systematics

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Spermatophytes

Angiosperms~300K spp

(e.g., magnolias, lilies, oaks, orchids)

Gymnosperms~881 spp

(cycads, ginkgoes, conifers)


1. Gymnosperms

Spermatophytes

Angiosperms~300K spp

(e.g., magnolias, lilies, oaks, orchids)

Gymnosperms~881 spp

(cycads, ginkgoes, conifers)


~250 spp

1 sp

~630 spp

1. Gymnosperms

2. Ancienta. Among the oldest of spermatophytes


Jurassic Diorama. Credit: Alfred F. Harrell , 1977 (Smithsonian Institution)

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2. Ancienta. Among the oldest of spermatophytesb. Predated & outlasted the dinosaurs


2. Ancienta. Among the oldest of spermatophytesb. Predated & outlasted the dinosaursc. Help tell story of changing Earth




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Gondwana

I. Cycads StoriesC. Ecology

1. Pollination


1. Pollination• Dioecious (no selfing)• Strobili are fruit-scented• Beetles pollinate

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1. Pollination2. Seed dispersal

• Fleshy & colorful seed coat attracts various vertebrates.


1. Pollination2. Seed dispersal3. Herbivory defense

•Various toxins in all parts, concentrated in pollen and seeds.

I. Cycads StoriesD. Economic Botany & Ethnobotany

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1. Ornamental• Aesthetic• Mystique of age & rarity


1. Ornamentals2. Food & medicine

e.g., Seeds with large, starchy gametophyte.e.g., Bioactive chemistry (toxins) in low doses

have various medicinal applications.

I. Cycads StoriesE. Conservation

1. All cycads are CITES Appendix I or II (cites.org) (cites.org)

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1. All cycads are CITES Appendix I or II (cites.org)

a. 98 spp on I


1. All cycads are CITES Appendix I or II (cites.org)

a. 98 spp on I

b. 252 spp on II


1. All cycads are CITES Appendix I or II (cites.org)2. Illegal trade > 10 billion USD (Pittman 2005)?

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1. All cycads are CITES Appendix I or II (cites.org)2. Illegal trade > 10 billion USD (Pittman 2005)?

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1. All cycads are CITES Appendix I or II (cites.org)2. Illegal trade > 10 billion USD (Pittman 2005)?3. USFW enforces CITES domestically

Australian Author, International Felon

Operation Jurassic (1998; halted > 200K USD)Operation Botany (1999-2001; halted > 840K USD)

F. Cycads & Guam ALS-PDC

1. Guam1898-1941 (US territory)1941-1944 (Japan)1944-present (US)


2. ALS-PDC (lytico-bodig)

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a. Symptoms: • Progressive neurodegenerative disease• Lytico = Prog. paralysis resembling Amyotrophic Lateral Sclerosis• Bodig = Parkinsons w/ Alzheimers-like dementia



a. Symptoms: • Progressive neurodegenerative disease• Lytico = Prog. paralysis resembling Amyotrophic Lateral Sclerosis• Bodig = Parkinsons w/ Alzheimers-like dementia

b. Prognosis: death < 10 yrs from diagnosis.


3. Chamorro

a. Historically very healthy

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3. Chamorro

a. Historically very healthy

b. ALS-PDC epidemic


4. NIH (1940s-1990s)


4. NIH (1940s-1990s)

a. Genetic Hypothesis

1) Evidence for• Endemic to the Chamorro culture• Primarily in men

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4. NIH (1940s-1990s)



2) Evidence against?


4. NIH (1940s-1990s)



2) Evidence against?• Why now?• Chamorro immigrants & emigrants• BMAA in the brain associated w/ neurofibrillary

tangles & atrophied neurons

BMAA

• Protein amino acid• Major neurotransmitter

• Non-protein amino acid• In cycad pollen & seeds • Excitoxic agonist of GLU• Likely anti-herbivory defense

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4. NIH (1940s-1990s)

a. Genetic Hypothesisb. Cycad Hypothesis (1970s-1990s)

1) Evidence for• Neurotoxic BMAA in cycad seeds & pollen• Flatbread, dumplings made from seeds


4. NIH (1940s-1990s)



2) Evidence against?


4. NIH (1940s-1990s)



2) Evidence against?• Chamorro doing this for centuries.• Chamorro pre-treat the seeds to remove BMAA

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4. NIH (1940s-1990s)

a. Genetic Hypothesisb. Cycad Hypothesis (1970s-1990s)c. APS-PDC fading away, NIH gives up (1990s)


5. Cox & Sacks (2002) Neurology 58: 956.


5. Cox & Sacks (2002)a. Oliver Sacks (1933-2015)

• Neurologist• Discovered, 1969, that L-Dopa

(dopamine precursor) could “awaken” catatonic survivors of the 1917-28 encephalitis lethargica epidemic.

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5. Cox & Sacks (2002)a. Oliver Sacks (1933-2015)

• Neurologist• Discovered, 1969, that L-Dopa

(dopamine precursor) could “awaken” catatonic survivors of the 1917-28 encephalitis lethargica epidemic.

• Author

19901973

1985

1997

• ALS-PDC fading away• Cycads likely involved but how?


5. Cox & Sacks (2002)b. Paul Cox

• Botanist• Then, Inst. Ethnobotany, NTBG, Hawaii• Now, Inst. Ethnomedicine, Wyoming

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5. Cox & Sacks (2002)c. A new angle on the Cycad Hypothesis



XX ??F. Cycads & Guam ALS-PDC


XX

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XXRoot symbionts(cyanobacteria) make the BMAA Cox et al. 2003. PNAS 100: 13380.



Biomagnificationof BMAA

Cox et al. 2003. PNAS 100: 13380.



Cycad-Bat Hypothesis explains: • Immigration & emigration phenomena• Sex bias

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Cycad-Bat Hypothesis explains: • Immigration & emigration phenomena• Sex bias• Increase & decline of ALS-PDC in 20th century



Cycad-Bat Hypothesis explains: • Immigration & emigration phenomena• Sex bias• Increase & decline of ALS-PDC in 20th century


5. Cox & Sacks (2002)d. Since 2002

1) Protein-boundBMAA

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1) Protein-boundBMAA2) BMAA & Alzheimer’s in N America



1) Protein-boundBMAA2) BMAA & Alzheimer’s in N America3) Cyanobacteria occur globally.

II. ConclusionsA. Cycads are a microcosm for importance of botany

• Food, medicines, habitat, recreation, fuel, shelter, culture & commerce.• Ignore them or their biology at your peril.

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• Food, medicines, habitat, recreation, fuel, shelter, culture & commerce.• Ignore them or their biology at your peril. • Basic research has unforeseen payoffs.



B. Zoology, medicine, law, etc. highly incomplete w/o botany




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C. Importance & versatility of plants emerge from their role as producers




C. Importance & versatility of plants emerge from their role as producers

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