GEOGRAPHICAL VARIATION IN THE STUDY OF BIOGEOGRAPHY

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Blackwell Science, LtdOxford, UKDDIDiversity and Distributions1366-9516Blackwell Science, 2000632000168BibliodiversionsBibliodiversionsBibliodiversions205215Graphicraft Limited, Hong Kong

70 MILLION YEARS OF VEGETATION DYNAMICS

Graham, A. (1999)

Late Cretaceous and Cenozoichistory of North American vegetation.

OxfordUniversity Press, New York. xviii + 350 pp, tables,figs, photos, index. Hardback: Price US$95.00,ISBN 0 195 11342 X.

Why are the great plains of North America domin-ated by grassland vegetation? What are the originsof Tundra and Boreal forest? How have innova-tions in palaobotany, palynology and biogeographyaided our understanding of the origins, affinitiesand evolution of the major North American plantformations? These questions are among the cent-ral issues explored in Graham’s comprehensiveand excellent book on the Late Cretaceous andCenozoic history of North American vegetation.The principal aim of the book, to explain theorigin and development of North American plantformations, is clearly defined at the onset andremarkably well achieved considering the broadscope. In Chapter One, the reader is provided witha descriptive overview of the seven major plantformations that exist in North America today,thereby setting the scene for the book as a whole,but also constituting the end point of the complexand dynamic vegetation history that unfolds inthe subsequent chapters. In Chapters 2, 3 and 4,Graham provides the essential contextual frame-work of the environmental changes that haveoccurred over the last 70 million years, the tim-ing of these events, and the methodologies andconcepts used to investigate vegetation history.In the subsequent three chapters, an impressivelist of fossil floras are discussed in time slices[Late Cretaceous to Early Eocene (Chapter 5),Middle Eocene to Early Miocene (Chapter 6),Middle Miocene through Pliocene (Chapter 7) andQuaternary, (Chapter 8) ] in relation to the majorfactors that have influenced their distributionand composition, such as climate change, sealevel oscillations, and tectonic processes. In addi-tion to this complex web of interacting factors,the origin and development of vegetation throughtime are examined in relation to coeval faunal events.Chapter 9 finally synthesizes the formidable amount

of information, to analyse critically the biogeo-graphical affinities of North American vegetation.

Throughout the book, there is a strong themewhich emphasizes the need to combine all of themany threads of evidence present in the fossilrecord, be it isotopic, biological or geological inorder to attain a comprehensive view of the majorsteps in vegetation dynamics. This is reiterated inthe final chapter where Graham reviews emer-ging techniques in biogeography and outlines keyareas for future research, both of which, are verymuch collaborative in nature. The book is verywell structured, well referenced at the end of eachindividual chapter and although many disparatetopics have been covered, the majority have beendealt with comprehensively and are well up to date.

The targeted audience ‘both specialists andgeneralists who share an interest in the envir-onments and events that have shaped NorthAmerican vegetation’ at first seems slightly overambitious as it is so difficult to cater equally foran audience of such a broad spectrum. Certainly,the inclusion of helpful summary sections, tablesand explanations will suit the generalist and theimpressive amount of detail covered and extens-ive references will provide plenty of fodder forthe specialist. However when all is weighed upin relation to the price at US$95, I think thebook will appeal more to the graduate than theundergraduate and I suggest that University andInstitutional libraries will be the most likelybuyers. For the more advanced undergraduate,this book will most certainly provide the biologist/botanist with an all important long-term tem-poral perspective of the complexities of vegetationhistory, and the geologist with an insight of theimpacts of geological events on communitydynamics.

I also have a minor quibble with the figures asunfortunately, although their content is generallygood, the quality throughout is quite poor and inplaces lets the book down. For instance, there areonly two colour plates in the entire book, whichconsidering the price, is disappointing. Colourphotographs would have been much more helpfulin giving a general impression of the differentformation types in Chapter 1, rather than the

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rather greyish figures provided. In Chapter 2however, a myriad of factors influencing andinteracting with vegetation are skillfully woventogether by the inclusion of a new factor as it isintroduced in the text, into an increasing complexflow diagram. Although the quality of reproduc-tion of these flow diagrams seems poor, they workvery well at simplifying the huge amount of con-text information reviewed. In Chapters 5, 6 and 7,figures containing lists of the major fossil florasinvestigated in each of the three time slices, havebeen superimposed in a temporal sequence onpalaeotemperature and sea level curves. Oncemore, the excellent content of these figures issomewhat let down by their poor quality.

Finally, I feel that the important concepts offormations and associations used to describeunits of vegetation throughout the book shouldhave been discussed more critically at the start,particularly for the benefit of the geologist orundergraduate who may not be familiar witharguments for and against such a classificationsystem. Graham does outline that these conceptshave their problems as the book proceeds, butleaves the critical discussion that associations aredynamic and consequently so too is vegetationhistory to the final chapter. Notwithstanding, Ithink this is a great book which will serve as anexcellent guide for an advanced lecture course andas a palaeobotanical guide to the localities ofNorth America. I also like the personal asides andsnippets of information on the history of thepeople and techniques that have brought thisfield of research to where it is today.

JENNIFER C. McELWAIN

Department of GeologyThe Field MuseumChicagoU.S.A.

632000168BibliodiversionsBibliodiversionsBibliodiversions100Graphicraft Limited, Hong Kong

FUTURE OF THE TROPICAL NATURE: WORST NEWS EVER

Terborgh, J. (1999)

Requiem for nature.

IslandPress/Shearwater Books, Washington, DC. xii +234 pp, figs, index. Hardback: Price $24.95.ISBN 1 559 63587 8.

‘From my earliest days as a preschooler,my abiding obsession has been discovering and

appreciating nature … My goal was to dis-cover all the snakes, turtles, salamanders, birds,mammals, and what-have-you … The thrill ofeach new find contributed to a buddingknowledge of natural history.’

These introductory sentences by John Terborgh,Professor of Environmental Science and Botanyand co-director of the Center for Tropical Con-servation at Duke University, could have beenwritten by another famous naturalist, ErnstThompson Seton. I am sure that Terborgh, likemost of us, also read his books. However, Setonwas lucky to live one century earlier when thelandscape of his boyhood was not destroyed bybulldozers during his lifetime. All changes weremuch slower at the beginning of the last century.Now, all human-caused transformations of ourplanet are accelerating, especially in countries withfast population growth, unstable societies, weakinstitutions, and inadequately protected areas.Incidentally, those are essentially the same countrieswhere most of the terrestrial biological diversityis, or was, concentrated: countries possessing whatis left of tropical forests.

Can money from agencies like USAID or theinternational banks help? Yes, but it would haveto be done differently than in the last decades.A seemingly logical assertion that ‘the real threatto wildlife is poverty, not poaching’ has beenrepeated many times (e.g. Attfield, 1999). How-ever, fashionable attempts to integrate economicdevelopment with conservation have failed toprotect tropical forests. By stimulating the localeconomy, so called ‘integrated conservation anddevelopment project’ typically attracts newcomersto a park’s perimeter, thereby increasing the externalpressure on the park’s resources. Development-oriented conservation projects, relying on largeamounts of foreign money, often ignore the implica-tions of the fact that much forest exploitationis conducted by recent immigrants who have nolong-term commitment to the area they are exploit-ing. Using examples from tropical countries aroundthe world, Terborgh shows that what is called‘progress’ and ‘sustainable development’ by many,is in fact an unprecedented destruction of natureand a recipe for extinction of species. Based onmore than 30 years’ experience as a primate eco-logist in West Africa, Oates (1999) comes to thesame conclusion. Two important issues, reduction

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of poverty and biological conservation, have beenconfused.

Terborgh’s ‘nature’ is the web of interac-tions among species, the continuity of processesin human-undisturbed ecosystems. Terborgh hasused many opportunities to study species inter-actions: from pristine forests of Manu NationalPark in Perú, through somewhat simplified foreston Barro Colorado Island in Panama, to bizarreremnants of animal communities in forest frag-ments on islets in Lago Guri in Venezuela.Chapter 7, where some relevant results of hisfield studies are summarized, reads like a detect-ive story. To preserve biodiversity means tomaintain the web of interactions that regulatesand perpetuates the ecological system. Unfor-tunately, many of the world’s parks are notlarge enough to maintain populations of toppredators; they are unable to sustain the fullspectrum of ecological functions needed to pre-serve biodiversity.

Still, any park, as long as it is really protected,is better than no park. But who will pay? Thesituation is somewhat easier with savanna parkswith high densities of big mammals. Here, tourismcan be a source of badly needed money. Tropicalforests are much less attractive. A good startingpoint would be to establish national conservationtrust funds, essentially endowments in support ofparks. Trust funds (some already have been createdin Bhutan and Mexico) offer an enormous advant-age over short-term projects (see also Southgate,1998). The key, however, is law enforcement.Adequate financing in itself does not guaranteesuccessful parks if enforcement is not rigorouslyimplemented. Exposing the gloomy status of trop-ical forest national parks across three contin-ents (many are essentially just on paper, some are‘empty’ without any larger edible animals, othersare illegally logged or encroached), Terborghconcludes that enforcement is the

sine quanon

of biodiversity preservation. Local peopleshould be involved as it really helps in the longrun. A bottom-up approach as exemplified bycommunity-based conservation can work undersome fortunate circumstances (Western, 1997),however, biodiversity transcends national bound-aries and belongs to no one. It belongs only tothe planet Earth.

The most radical, but very likely the onlypotentially successful option would be full inter-

nationalization of nature protection. If peace-keeping has been widely accepted as a functionof the United Nations, why not nature keeping?Internationally sponsored guards would be inde-pendent of local pressures and thus better ableto exercise authority. This seems to be the onlysolution. However, as Terborgh knows very well,this will not be easy to realize. Even much lessambitious international conservation projects intropical countries have already been labeled as‘ecocolonialism’ (Southerland, 1998). Fortunately,not everybody feels that way. For example, MarioBoza, former Director of National Parks and ViceMinister of Natural Resources, Energy, and Minesin the government of Costa Rica, already hadthis clear vision: ‘Many organizations use fundsto maintain an international bureaucracy ratherthan supporting direct conservation in the field …International environment standards should be setby a United Nations environmental organizationthat is empowered to infringe on sovereignty ofindividual states in environmental matters’ (Boza,1993). However, if the international nature keepingturns out to be unrealistic, than, I am afraid, thetitle of Terborgh’s book is accurate.

MARCEL REJMÁNEK

Section of Evolution and EcologyUniversity of CaliforniaDavis,CaliforniaU.S.A.

REFERENCES

Attfield, R. (1999)

The ethics of the global environ-ment

. Prude University Press, Western Lafayette,Indiana.

Boza, M.A. (1993) Conservation in action: past,present, and future of The National ParkSystem of Costa Rica.

Conservation Biology

,

7

,239–247.

Oates, J.F. (1999)

Myth and reality in the rain forest.How conservation strategies are failing in WestAfrica

. California University Press, Berkeley.Southerland, A. (1998)

The making of Belize. Global-ization in the margins

. Bergin & Garvey, Westport,Connecticut.

Southgate, D. (1998)

Tropical forest conservation. Aneconomic assessment of the alternatives in LatinAmerica

. Oxford University Press, Oxford.Western, D. (1997)

In the dust of Kilimanjaro

.Island Press/Shearwater Books, Washington,D.C.


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A MUST FOR NORTH AMERICAN BIOGEOGRAPHERS

Kartesz, J.T. & Meacham C.A. (1999)

Synthesisof the North American Flora, Version 1.0.

NorthCarolina Botanical Garden, University of NorthCarolina, Chapel Hill, North Carolina, USA.CD-ROM interactive software. Price $495.00.ISBN 1 889 06505 6.

One CD instead of a library? Not yet. Keys,descriptions, and illustrations of individual taxaare not here, but, on the other hand, there is anincredible amount of information on this CD-ROMthat is not available immediately in any library:distribution maps for each of the 293 famil-ies, 3303 genera, 22 006 species, 2735 subspecies,5512 varieties, and 993 hybrids based on theirpresence/absence in 70 areas of North Americaand nearby islands (U.S. states including DC andHawaii, Canadian provinces, Puerto Rico, U.S.Virgin Islands, Greenland, and the French islandsSt Pierre and Miquelon) can be stored and printed.Source information for individual taxon-arearecords is provided instantly using ‘mouse-over’ tech-nique (e.g. reference to authoritative publication,unpublished sources, or personal communications;information about voucher specimens is oftenalso included).

The valid Latin name of each taxon is accom-panied by a common name and list of relevantsynonyms with authors. Synonyms can be dis-played either hierarchically, within the acceptedtaxonomy (checklist format), or alphabetically(thesaurus format) for easier access. All informa-tion which was in Kartesz (1994; now out of print)is here and updated.

For each of the 70 areas, information on totalnumbers of all taxa is provided. Using 135‘biological attributes’, this can be decomposedinto more specific information on numbers ofnative and exotic genera or species, species orgenera in particular families, extinct taxa, etc.Information on individual areas and taxon attri-butes can be combined in many meaningful ways(Table 1). Lists of taxa produced by these opera-tions (e.g. exotic wetland plants of Kansas, toxicplants of Gulf coast states, or Cactaceae spe-cies in the Arctic) can be stored and printed.Relative concentration of selected sets of taxa canbe depicted graphically via maps with propor-tional shading. Information about actual numbers

of taxa in individual areas is provided instantlyby clicking on a desired area (e.g. 60 out of 970native monocot species present in California shouldbe also in Greenland).

This project was not an easy task. Consider-ing that the most recent floras or checklists forsome areas are quite old (e.g. Alabama: 1901,Idaho: 1952, Mississippi: 1921, Saskatchewan: 1944),their updating was an enormous challenge. It isimpossible to tell how many sources, publishedand unpublished, were used for creation of thissystem. I spent a substantial amount of timetrying to find some publications that were missed.However, I gave up when I realized that not onlydid this monumental synthesis contain informationon spontaneous regeneration of

Laurus nobilis

in San Francisco from Thomas’

Flora of theSanta Cruz Mountains

, but also information fromthe new

Steyermark’s Flora of Missouri

(Vol. 1,1999) and articles from

the Bishop Museum Occa-sional Papers

(1998). Well, there are two afterall: (1) Wunderlin’s (1998)

Guide to the VascularPlants of Florida.

Here we have an interesting dis-crepancy: Wunderlin’s total number of species forFlorida is 3834 while

Synthesis’

total is 4139;moreover, this discrepancy is not due to exoticspecies because Wunderlin’s number is higher:1180 vs. 1035; (2)

Vascular Flora of Rhode Island

(Gould

et al.

, 1998). A similar discrepancy is hereas well:

Synthesis’

total number of species is 1941,while in the

Flora

the total number is 1618; inthis case, numbers of both native and exotic spe-cies are substantially higher in the

Synthesis

. Asreported numbers for British Columbia (Table 1)are also much higher than numbers in recentchecklists for the province (Douglas

et al.

, 1994;Qian & Klinka, 1998), my impression is that

Synthesis’

lists are highly inclusive.Considering that this is version 1.0, there are

only very few problems I can report: (1) ‘Exotic’taxa include only established non-native taxa thatare native outside of the all the 70 areas coveredby the

Synthesis.

State- or province-level nativityis not considered in this version; (2) ‘Weeds’ aredefined in the

Synthesis

as plants that generallygrow in disturbed areas

or

in areas where they areunwanted and unappreciated. Two overlappingbut nonidentical categories (colonizers and weeds)are mixed here.

Betula nana

is classified as a‘weed’ but

B. pendula

is not. I would expectthat the opposite should be the case. For exotic


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species, weeds, and related concepts, more carefulterminology and categorization should be used(see Richardson

et al

. 2000); (3)

Striga asiatica

hasbeen contained but not eradicated in Carolinas(Kaiser, 1999); probably all that is referred toas

Rubus discolor

Weihe & Nees (Himalayanblackberry) is

R. armeniacus

Focke (Weber, 1995);

Conyza sumatrensis

(Retz.) E. Walker is prob-ably the valid name for the species listed as

C. floribunda

Kunth (Stace, 1997) or, at least, itshould be listed as a synonym;

Prunella vulgaris

ssp.

vulgaris

is not native;

Anona cherimola

ismisspelled.

I hope that following versions will includeamong ‘biological attributes’ also chromosomenumbers and ploidy status, modes of fruit /seeddispersal, and descriptions of total distribution(beyond the 70 areas covered) of all species andsubspecific taxa. British

Ecological Flora Database

(Fitter & Ford, 1993) can serve as a source ofinspiration for which other biological attributescould be considered. Also, I hope that one day

Table 1 Examples of phytogeographical characteristics which can be readily calculated using Kartesz &Meacham’s (1999) Synthesis. R stands for restricted taxa not found outside of the area. R, –, +, and*(intersection) are operators available in the ‘Query’ menu of the program. a = number of species sharedby two areas, b = number of species present only in the first area, and c = number of species present onlyin the second area (quantities a, b, and c are used in Table 2)

States, provinces, or their combinations Number of species their combinations

Total Native Exotic1

Alaska 1535 1360 175British Columbia 3009 2353 656R Alaska 71 66 5R British Colombia 23 9 14Alaska * British Columbia (= a) 1274 1119 155Alaska – British Columbia (= b) 247 227 20British Columbia – Alaska (= c) 1721 1223 498Alaska + British Columbia 3256 2583 673R Alaska + British Columbia 108 89 19

Yukon – (Alaska + BC + Mackenzie)2 12 11 1(Alaska * BC * Mackenzie) – Yukon3 54 41 13

Atlantic coast (Greenland/Florida) 8293 5889 2404Atlantic coast * Gymnosperms 53 36 17Pacific coast (Alaska/California) 8617 7096 1521Pacific coast * Gymnosperms 73 70 3

All areas covered by the Synthesis 22 006 18 258 3748Single area occurrence 7612 6237 1375Extinct 166 166 0Trees + Shrubs – (Trees * Shrubs)4 3379 2709 670Asteraceae * Trees * Single area occ. 11 9 2

Continental USA 18 510 15 407 3103Single state occurrence 4811 3969 842Rafflesiaceae 1 1 0Extinct 57 57 0

1 Calculated as (Total – Native): this quantity includes only those exotic species that are not represented bynative subspecific taxa or populations. 2 Number of species present in Yukon but not found in Alaska,British Colombia, or Mackenzie. 3 Number of species shared by Alaska, British Colombia, and Mackenziebut not found in Yukon (we should go and look for them; most of them must be there!). 4 All species thatare classified as trees and/or shrubs are counted only once.


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more natural boundaries than state and provinceborders will be used for delimitation of physio-graphic regions (e.g. Rockies or Great Basin).Finally, some indices of floristic similarity (e.g.Jaccard and Preston’s z) could be incorporatedinto the program.

Extremely positive reviews of the

Synthesis

are appearing in professional periodicals (e.g.A. Ceska:

Bulletin of the Ecological Society ofAmerica

81/2

, 124–125; R. Cranfill:

Taxon

49

,142–145; H.D. Wilson:

Systematic Botony

25

, 150–152). Instead of recycling the many superlativesalready used, I will try to show how informationin the

Synthesis

can be used for one practicaltask, which may be interesting for all readersof this journal. How much is North Americanflora homogenized due to naturalized species?Table 2 illustrates what we can derive from the

Synthesis

. Neighbouring areas are, due to exotic

species, consistently somewhat more dissimilarand remote areas are more similar. Obviously,the answer to our question is scale-dependent.Without the

Synthesis

, it would be not conceiv-able to get a complete understanding of what isgoing on.

This is one of the most user-friendly computerpackages I have ever encountered. Minimum sys-tem requirements are Pentium 90 MHz-class pro-cessor, 32 MB RAM, 25 MB free hard drive space,and SVGA display (800 by 600 pixel resolution)with 16 colours. The program is designed for IBM-compatible computers running Windows 3.1, 95,98, NT, or 2000. It also runs extremely fast onPower Macintosh computers with PC compatibilitycards. Taxonomic, nomenclatural, phytogeographic,and other updates are on http://www.bonap.org.The

Synthesis

can be ordered from the NorthCarolina Botanical Garden, Campus Box 3375,

Table 2 Similarity of North American floras expressed as Jaccard’s coefficient of similarity J = 100*a/(a + b + c) (see Table 1 for definition of symbols). J ranges from 0% (no species in common) to 100%(identical floras). In each group of areas, the first pair are direct neighbours and the second pair aredistant (>1000 km) areas. In terms of species presence/absence, exotic plants are making geographicallyclose areas more distinct while distant areas are becoming more similar to each other

Combination of states Similarity of composition (J) or province

Total Native Exotic

Alaska vs. British Columbia 39.3 < 43.6 > 23.0Alaska vs. California 9.7 > 9.3 < 11.8Arkansas vs. Louisiana 54.2 < 56.5 > 45.8Arkansas vs. S. Carolina 46.4 > 45.9 < 48.8California vs. Nevada 35.9 < 38.2 > 24.2California vs. Texas 11.9 > 9.0 < 30.1Florida vs. Georgia 49.3 < 53.9 > 34.1Florida vs. Puerto Rico 19.1 > 16.4 < 28.8Kansas vs. Oklahoma 59.3 < 61.2 > 50.1Kansas vs. New Brunswick 19.5 > 15.7 < 35.0Manitoba vs. Saskatchewan 63.1 < 65.4 > 53.1Manitoba vs. Tennessee 17.5 > 15.5 < 27.0Minnesota vs. Ontario 58.2 < 63.9 > 44.5Minnesota vs. Greenland 10.1 > 7.8 < 21.3New York vs. Pennsylvania 69.8 < 75.6 > 59.1New York vs. Alberta 19.7 > 18.8 < 22.1S. Carolina vs. N. Carolina 72.6 < 76.6 > 57.2S. Carolina vs. Quebec 19.5 > 18.0 < 25.2Washington vs. Oregon 62.2 < 62.6 > 60.6Washington vs. New Hampshire 20.5 > 15.6 < 41.6


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Totten Center, University of North Carolina atChapel Hill, Chapel Hill, North Carolina 27599–3375. Credit card orders may also be placed atTel. +1 919 962 0578.

The

Synthesis of the North American Flora

is amilestone nomenclatural reference, floristic atlas,and, above all, a remarkable analytical tool. AllNorth American plant taxonomists, phytogeo-graphers, and plant macroecologists should havethis program on their computers. It is worthy ofthe price (but it could be cheaper!).

MARCEL REJMÁNEK

Section of Evolution and EcologyUniversity of CaliforniaDavisCaliforniaU.S.A.

REFERENCES

Douglas, G.W., Straley, G.B. & Meidinger, D. (1994)

The Vascular Plants of British Columbia. Part 4Monocotyledons

. Ministry of Forests, Victoria,British Colombia.

Fitter, A. & Ford, H. (1993) The Ecological FloraDatabase.

Bulletin of the British Ecological Society

,

24

, 7–14.Gould, L.L., Enser, R.W., Champlin, R.E. &

Stuckey, I.H. (1998)

Vascular flora of Rhode Island:a list of native and naturalized plants

. RhodeIsland Natural History Survey, Kingston, RI.

Kaiser, J. (1999) Stemming the tide of invading spe-cies.

Science

285

, 1836–1840.Kartesz, J.T. (1994)

A synonymized checklist of thevascular flora of the United States. Canada, andGreenland, Vol. 1 and 2

, 2nd edn. Timber Press,Portland, Oregon.

Qian, H. & Klinka, K. (1998)

Plants of BritishColumbia

. UBC Press, Vancouver.Richardson, D.M., Pysek, P., Rejmánek, M.,

Barbour, M.G., Panetta, F.D. & West, C.J. (2000)Naturalization and invasion of alien plants: con-cepts and definitions.


6

, 93–107.Stace, C. (1997)

New flora of the British Isles

, 2ndedn. Cambridge University Press, Cambridge.

Weber, H.E. (1995)

Gustav Hegi Illustrierte Floravon Mitteleuropa

. Band IV, Teil 2A. BlackwellWissenschafts-Verlag, Berlin.

Wunderlin, R.P. (1998)

Guide to Vascular Plants ofFlorida

. University Press of Florida, Gainesville,Florida. [See also http://www.plantatlas.usf.edu/–

Atlas of Florida Vascular Plants

. 2000 Institutefor Systematic Botany, University of SouthFlorida.]


‘OUR BEST FRIENDS AND CLOSE ASSOCIATES’. ALIEN SPECIES ON THE NORTH AMERICAN BATTLEGROUND

Cox, G.W. (1999)

Alien species in North Americaand Hawaii: impacts on natural ecosystems.

IslandPress, Washington. xii + 387 pp, tables, glossary,index. Hardback: Price US$60.00. ISBN 1 55963679 3. Paperback: Price US$30.00. ISBN 1 55963680 7.

In the clear, concise style characterizing Cox’sprevious texts from his Dynamic ecology (1973)to Conservation biology: concepts and applications(1997), his latest work, Alien species in NorthAmerica and Hawaii: impacts on natural ecosystems,constitutes a comprehensive synthesis of the his-tory, distribution, impacts, management initiativesand policy dilemmas of some the most noxiousintroduced species in the 10 most seriously affectedregions of the United States. Canada is treated toa much lesser degree and Mexico is mentioned inpassing on only six occasions.

The stated objective of the book is ‘to evaluateexotic invasions of North America in the light ofthe emerging science of invasion ecology’, andto ‘examine the seriousness of the threat of theseinvaders to North America, and what can be doneto reduce this threat.’ As the subtitle suggests, thebook is not a dispassionate evaluation of exotics.Rather, it attempts to fill the ‘education gap’between concerned environmentalists and ‘the pub-lic at large [that] remains largely unaware of theseriousness of the threat’ to the native flora andfauna of North America, ‘the largest battlegroundin the global war against invasive exotics.’ Theapproach is nonmathematical, better described asa descriptive catalogue than an analytical treatize.

For the layperson, the book provides numerousexamples of aggressive exotics from representat-ive biomes of North America, the full range ofinvaders (plants, plant diseases, marine inverteb-rates, terrestrial invertebrates, insects, freshwaterfish and terrestrial vertebrates) and across a broadrange of habitat types (bays, estuaries, lakes, riversand streams, forests, tropical and semitropicallowlands, plains and intermontane grasslands,floodplains, mediterranean ecosystems, and islandecosystems). In addition to the litany of geograph-ically referenced species accounts, also presentedare their myriad impacts in clear nontechnical


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language, as well as a cursory review of existinginvasion theory. A short, but well-conceived,glossary clarifies technical terms and theoreticalconcepts. To its merit, the book considers impactsbeyond simply those on charismatic or priorityconservation species, also presenting communityand ecosystem level impacts. The most significantcontribution for the technical audience is theextensive cataloguing of exotics and their impactsbased on a thorough and well-referenced reviewof both historical and current publications; manyreferences come from the 1999 primary literature.Also useful is a three-page listing of internet sitesdedicated to exotic species.

The book is divided into five parts with eachof the 21 chapters being introduced with effectiveand engaging case studies that present key con-ceptual issues to follow. Part I provides the his-torical and conceptual background upon whichthe regional treatments of Part II are based. Herethe uninitiated receive a ‘crash course’ in inva-sion ecology ranging from the source, identityand attributes of some classic invaders such asthe zebra mussel (Dreissena polymorpha), the his-tory of exotic species introductions and theirstudies with the de rigeur references to Elton’spioneering work The Ecology of Invasions by Animals& Plants (1958) and Carson’s Silent Spring (1962),and the magnitude of ecological and economicimpacts of ‘biotic pollution.’

The comprehensive 10 regional treatment chap-ters of Part II constitute the bulk of the book.Spanning the whole of the United States anddrawing on examples from the primary liter-ature, Cox demonstrates convincingly that notall ecosystems are equally invasible and no singletheory can account for invasions and their impacts.For example, reviewing case studies from hishome state, California, it is argued that speciesrich areas commonly considered more ‘stable’and less invasible are in some instances highlyvulnerable to aggressive exotics from a range oftaxa. While the impacts of exotics are most evidentin Hawaii where they have occasioned both docu-mented extinctions and quantifiable ecosystemfunction disruption, Cox emphasizes that ‘unpre-dictability is a key feature in invasions’ and thatthey often lead to unforeseen outcomes such as‘food web chaos’.

Part III introduces some of the dilemmas createdby exotic species, associated impacts and their

management. Deliberately introduced game spe-cies, such as the brown trout, ring-necked pheas-ant and sika deer are often seen as desirable.Likewise, control of native North American spe-cies with anthropogenically extended ranges isfraught with controversy. Finally, a chapter dedic-ated to problems associated with domesticatedspecies gone feral, ‘our best friends and closestassociates’, provides a vivid example of the manyconflicting issues of ecology and ethics. In particu-lar for the lay audience, this section constitutesan effective means of tempering the knee-jerkresponse of ‘why isn’t anyone doing anything?’that many of the preceding examples may haveprovoked. Additionally it demands that the readerconsider his own role in species introductions andtheir control.

Whereas the regional treatment briefly intro-duces some theoretical aspects of invasion ecology,Part IV is specifically dedicated to this purpose.The format is standard (invader attributes anddifferential ecosystem vulnerability) and the the-ories presented are well known to professionalecologists (variable invasibility of successionalstages, the relevance of assembly rules, nichebreadth and openness, and disturbance). However,this short section provides some of the most inter-esting reading and insightful commentary. Thevaried nature of impacts is also considered includ-ing abiotic ecosystem impacts such as those onhydrology and fertility to biotic impacts, includ-ing those on trophic structure or occasioned bygenetic swamping via hybridization between nativesand exotics. Surely a matter of opinion, the bookmay have benefited from this section occurringbefore the regional treatment thereby providing atheoretical backdrop upon which the many spe-cific case studies of Part II might be considered.

Cox boldly closes in Part V with a presentationof the economic implications of exotic species andmanagement options that exist to control them.The book concludes with an explicit review ofthe shortcomings of existing management institu-tions and their lack of integration and providesconcrete recommendations for the strengtheningof global and national organizations chargedwith exotic species management. He notes thesewill be increasingly called upon as invasionscontinue with cultural and economic globalizationand as their impacts become even less predictablein the face of global environmental change.


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Although the examples provided are confinedto North America, the wide range of climatesand habitat types considered makes the bookrelevant to those interested in biological invasionsfrom other areas. Being a discipline involvingrates of change over time, correlations involvingmultiple factors and subjects considered withina geographical context, the use of illustrations,figures and diagrams would have enhanced the well-conceived text. While useful data is frequentlypresented in tabular form, other graphic repres-entations are lacking. Given the importance ofscale and spatial context, maps in particular wouldhave been useful. Although the well-written textmight have benefited from the inclusion of suchgraphical conceptual aids, on the whole the bookrepresents a valuable contribution to the invasionliterature for lay and technical audience alike.No original data, results or theories to explain themany invasions are presented, but the book clearlyachieves the professed goal of reviewing the stateof alien invasions in North America in attemptingto fill the existing education gap between theinformed environmentalist and uninformed publicat large.

SCOTT HENDERSONSchool of Geography and the EnvironmentUniversity of OxfordOxfordU.K.

REFERENCES

Collier, B.D., Cox, G.W., Johnson, A.W. & Miller,P.C. (1973) Dynamic ecology. Prentice-Hall, Inc.,Englewood Cliffs, N.J.

Cox, G.W. (1997) Conservation biology: concepts andapplications. 2nd edn. McGraw-Hill, New York.


SEAWEEDS, SCIENCE AND SOCIETY: A ROMAN NOIR ON INTRODUCED CAULERPA TAXIFOLIA

Meinesz, A. (1999) Killer algae. The true tale of abiological invasion (translated by D. Simberloff).University of Chicago Press, Chicago. xvi + 360 pp,colour figs. Hardback: Price £17.50. ISBN 0 22651922 8.

This is a detailed description of the introductionof a green seaweed into the Mediterranean sea.

It is the personal view of a scientist who workedwith these algae before the introduction, andwho has witnessed and participated in the fulldebate, from the discovery of the first populationin the early 1980s to the present. It is fascinatingreading for all wanting to learn more about intro-duced, invasive species in the marine environment,and particularly for anyone with an interest inthe interactions between science and society. Thetext has been translated into an easily readableEnglish, from the original French, by a well-known expert on introduced species, DanielSimberloff. Some of the English is a little uncon-ventional, but this adds to the French flavourof the narrative.

The introduced Caulerpa taxifolia is a remark-able organism. It consists of a single cell, whichcan be many metres long, and spreads by frag-mentation and vegetative growth. It is such abeautiful, feathery, bright green plant that it hasbeen widely used in marine aquaria. Originallya tropical species, it is has now been shown thata genetically distinguishable strain developed inan aquarium, probably at Stuttgart, Germany.The strain is capable of very rapid growth and,most importantly, can survive lower temperaturesthan the original source alga. C. taxifolia containschemical deterrents, which prevent many grazersbeing able to consume it. According to ProfessorMeinesz, there is strong evidence that the invaderwas introduced from the Oceanographic Museumin Monaco. It has spread exponentially where ithas been found, and may pose an ecologicalthreat in much of the Mediterranean.

The preceding paragraph seems straightfor-ward, but many comments in it were, and someof them are, extremely contentious in scientific,quasi-scientific, media and political circles inFrance, Monaco, and further afield. Much ofthe book is concerned with the ‘polemic’ whichhas raged over this introduction for many years,and which shows little sign of abating (over 600articles so far). Cliques have been formed through-out, and I have even been warned by a colleaguethat comments I make in this review will bereworked and twisted! Much of the debate hasbeen pursued in the French media, and therehave been many claims and counter-claims ofscientists making statements simply to increasetheir share of research funds. The multitude ofcharacters in this colourful tale ranges from


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Jacques-Yves Cousteau, to a defrocked priest withMafia connections. Some of the nastier sectionsof the controversy have been between the groupof scientists of which Professor Meinesz is amain spokesman, and the group led by FrancoisDoumenge, who replaced Cousteau as Directorof the Museum in Monaco. This even led tolibel suits against the initial French version ofthis book. Doumenge won his case on appeal,was awarded one franc in damages, and severalpassages were removed.

Professor Meinesz undoubtedly cares deeplyabout marine ecology, and is convinced thatC. taxifolia is an enormous threat that couldhave been averted if attempts had been madeinitially to remove it. Many of the most unpleas-ant disagreements have centred around side issuesto the ecological problems — for example, is itreally C. taxifolia? (yes), does it really come froman aquarium? (yes), the Monaco Museum? (prob-ably). It seems to me that critical questions— how much of the seabed will eventually beinvaded and how will this affect the ecosys-tems concerned? — remain unresolved. Althoughstill growing rapidly in many areas, there is someevidence that healthy seagrass beds can resistCaulerpa colonization. There is, however, nodoubt that large areas of seabed have beentaken over by a virtual monoculture of thisbeautiful, unpalatable alien.

The book is too long, and some of the argu-ments get a little lost in the polemic. I alsofound the chronology occasionally difficult tofollow. It must have been a challenge to separ-ate sections on the biology of the alga from thepolitical discussion, when in the course of theinvestigations many of the ‘facts’ on the organ-ism were hotly disputed. The role of the media,and how scientists and officials used it, isdiscussed at length. The author uses the finalchapter to analyse the wider implications, thelack of weight given in the general debate tocritical scientific information, and evidence of thedemise of ecology and natural history, which heconsiders a real danger to biodiversity. ProfessorMeinesz seems to be a mélange of victim andperpetrator, as most are who find themselvesimmersed in a media debate. His funds from theFrench government have been cut, but he hasgained a great deal of exposure, scientific andotherwise.

Recently there has been evidence that a sec-ond species, Caulerpa racemosa, is invading theMediterranean. I look forward to ‘Killer Algae 2— The Reckoning’.

JOHN J. BOLTONBotany DepartmentUniversity of Cape TownSouth Africa642000073BibliodiversionsBibliodiversionsBibliodiversions100Graphicraft Limited, Hong Kong

GEOGRAPHICAL VARIATION IN THE STUDY OF BIOGEOGRAPHY

Spicer, J.I. & Gaston, K.J. (1999) Physiologicaldiversity and its ecological implications. BlackwellScience Ltd., Oxford. x + 241 pp, figs, index.Paperback: Price £29.50, ISBN 0 632 05452 2.

The underlying premise of this work is thatan accounting of the research completed to datewill inspire new lines of inquiry in biogeography.Unfortunately, from this side of the Atlanticthis approach appears particularly ‘old school’.Attempts to point out, in print, fruitful pathsfor life-long research initiatives by the nextgeneration of students are traditionally ignoredin America. Maybe this is a fault of the revolu-tionaries in the colonies, but this well-writtenbook suffers from a lack of inspiring rebel leader-ship. Rather than using the enviable expertiseof the authors to help students develop goodjudgement, the authors take a kingly approachand grandly suggest potential research topics(such as the laughable: ‘Is acclimatization bene-ficial?’) in a separate chapter. While there is muchgood about this book, there is a fundamentalmismatch between contemporary American bio-geography and the approach of the authors.

Today’s student of biogeography has the fullpower of searchable databases to generate listsof research articles that they need to read. Whatstudents need is focus and good judgement.Unfortunately, the authors appear to value longlists of citations. Instead of offering a few goodstories (to narrow the search) and weighing theevidence (good judgement being hard to pro-gramme into search engines) they instead generatelists and counts. For example, after citing thecrippling criticism of Felsenstein (1985) concerningstatistical tests to compare species across taxo-nomic groupings they write:


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It seems most natural, therefore, to use thespecies as the unit of analysis … the applica-tion of phylogenetic analyses allowing testablepredications on the evolution of such featuresas endothermy, aerobic capacity, metabolic rate,specialized nerve cell function and mamma-lian blood characteristics, has to a large extentinvigorated what has come to be known asevolutionary physiology (Elgar and Harvey,1987; Derrickson, 1989; Garland et al., 1991,1997; Diamond, 1992, 1993; Garlnad, 1992;McNab, 1992; Watson, 1993; Clard and Wang,1994; Garland and Adolph, 1994; Garland andCarter, 1994; Grueer and Bradely, 1994; Ruben,1995; Diaz et al., 1996; Dutenhoffer and Swason,1996; Ward and Seely, 1996; Wright et al., 1996;Alvers-Gomez and Hopkins, 1997; Bennett,1997; Mangum and Hochachka, 1998; Weibelet al., 1998). (p. 139)

I have two questions: (1) Are they dismissingFelsenstein by saying that as everyone else isdoing it, it must be okay?; and (2) What is oneto do with that long list of citations? Those cita-tions do justice to neither the fields mentionednor the researchers cited. Unfortunately this isnot an isolated case. Throughout the book con-troversies are characterized by one or two cita-tions and then the vote counting begins. No finaljudgement is explicitly made. Counting citationsas a means of making judgements is precisely whatis not needed in an age where computer searchesgenerate hundreds of citations.

With their encyclopaedic view of the field onehopes for delivery on a promise made in thePreface to explore ‘some significant contributionslying uncited and forgotten’. Later the authorsdescribe in detail how Rubner in 1883 developeda surface rule of energy metabolism that wasnot cited by Kleiber. This produced a series ofmisinterpretations that the authors outline indetail. They conclude that Kleiber’s celebratedmetabolic scaling rule is more ambiguous thanadvertised. Unfortunately this is old news. In aprominent paper in Science (West et al., 1997), notcited by Spicer and Gaston but within the range oftheir literature review, the ambiguity of empirically-derived metabolic scaling exponents is made moot.Rubner’s forgotten paper of 1883 is likely to remainforgotten, and an opportunity to show that the

crowd had headed in the wrong direction (witnessthe dozens of papers focused on empirical deriva-tions of the Kleiber relationship) was lost.

The effort of the authors to provide a largenumber of citations, substantial breadth to thecitations, and the introduction of authors notoften cited, has other unintended consequences.It appears that Spicer and Gaston were uncom-fortable citing more than just a few of any givenauthor. How else can one account for there beingonly one citation for Robert H. MacArthur,one for E. Mayr, two for G.A. Bartholemew,and only four for J.H. Brown? There are nonefor D.S. Simberloff, F.E. Clements, P.S. Nobel,G.G. Simpson, R.H. Whittaker, and E.O. Wilson.These are not just American heroes, they are theheroes of biogeography. Any book that attemptsto explain biogeography needs to consider theviews of the giants in the field no matter howwell-known their work.

In particular, their literature review shows aserious lack of consideration of population gen-etics. The authors realize this shortcoming bysaying, after noting the difficulties of studyingthe genetics of physiological differentiation betweenindividuals, ‘as neither of the present authors aregeneticists, an attempt to redress this imbalancewill not be made here.’

In summary, what was started with grand prom-ises and high hopes has ended accomplishing justthe reverse of what the authors intended. Thebook has been made obsolete by new electroniccitation retrieval systems and changes in howadvances in biogeography are made. The authors,by documenting their encyclopaedic knowledge ofthe literature have placed too much of their efforton being all inclusive. The result is that theyare a kilometre wide and a centimetre deep. Theislands protruding from their coverage (for examplethe relationship between population genetics andbiogeography) do inspire exploration as do theideas that run against popular opinion. In otherwords, the value of this book might be how itexposes what they didn’t write.

GEORGE STEVENSCape Cod Museum of Natural HistoryBrewsterMassachusettsU.S.A.


GEOGRAPHICAL VARIATION IN THE STUDY OF BIOGEOGRAPHY

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