Late Cretaceous and Cenozoic history of Latin American vegetation and terrestrial environments /Alan Graham.

2010·87.4 MB·English

by  Graham, Alan,

Late Cretaceous
Cenozoic History o/
and
Latin American
Vegetation Terrestrial
and
Environments
Alan Graham
vjj!/Missouri Botanical Gardto
,0 • *^»
—t-*2. cy+-^>--~e<_t
^e_ ^6a_
0-««wC ^-^cytyA-/^-' . >S~^l '
<y*sfc^(f * CL -^^=£e—^ *tj+tu>
syid-^C -Z*-*-~+-yf &+—0—JL^ J —.
(l-^-tkv, ^b—-i*—o ^-«--»*--^ g^.# &—<£- ->tu«-^6t^tr,
_Js^*^-^_ -w^e «^=c
S?l/~9 * ~^—-g^ ~J&-*JL
(L^X.
^ciu
du> Qr«
ISBN: 978-1-930723-68-9
Library of Congress Control Number: 2009935194
Monographs in Systematic Botany from the Missouri Botanical Garden, Volume 113
ISSN 0161-1542
Scientific Editor and Head: Victoria C. Hollowell
Managing Editor: Beth Parada
Associate Editor: Allison Brock
Editorial Assistant: Tammy M. Charron
Press Coordinator: Cirri R. Moran
Copyright © 2010 by Missouri Botanical Garden Press
PO. Box 299
St. Louis, Missouri 63166-0299, U.S.A.
www. mbgpress. org
All rights reserved. Printed in the U.S.A.
Frontispiece: Back on the road through the help of friends, between Atotonilco and Metquititla, Mexico, in August 1965.
The letter was written by the local schoolteacher, who made arrangements for work and accommodations, and it is symbolic
of encounters during the decades of the author’s field research in Latin America (see Preface). Photograph by the author.
Contents
Preface vi Chapter 5
References viii The Antilles 298
Prologue xi Notes 314
Notes xiv References 315
References xv
Chapter 6
Nomenclature xvii
Central America 319
Section I—Background
References 349
Geography • Geology • Vegetation Chapter 7
Chapter 1 South America 355
References 446
Lay of the Land—Climates and Physical Geography 3
Some General Aspects of Climate 3 Section III—Syntheses
Mexico 13
Chapter 8
The Antilles 17
Central America 22 The Broader Picture 479
South America 30 Closure of the Isthmus of Panama and the Biotic
Notes 51 Consequences 479
References 52 Origin of the Northern Temperate Element
in the Latin American Biota 482
Chapter 2
Paleovegetation and Paleogene Temperatures
Constructing the Landscape—Late Cretaceous and Cenozoic of Equatorial Waters 483
Geology of Latin America 60 Dust, Hurricanes, and Latin American-African Plant
Mexico 60 Affinities 484
The Antilles 67 A Subhumid Corridor 486
Central America 78 The Many Faces of Biogeography 486
South America 84 Reconciling Biogeographic Histories: Fossils
Notes 98 and Molecular-defined Lineages
References 99 in Rlobpphora 489
Chapter 3 Notes on Some Lineages 490
Origin of the Neotropical Rain Forest 498
Vegetation—Clas sification 111
Climate, Vegetation, and the Stability
Mexico 116
of Tropical Ecosystems 499
The Antilles 152
Refugia 500
C en tr al America 169
Notes 511
South America 183
References 512
Notes 216
Appendices
References 217
Section II—Database Appendix 1—Modern Plant Formations
and Representative Species 525
Late Cretaceous and Cenozoic Floras Appendix 2—Late Cretaceous and Cenozoic Plants
and Terrestrial Paleoenvironments Mentioned in the Text 559
2.1 Arranged by Age 560
Introduction 245
2.2 Arranged by Plant Group/Family 582
Chapter 4
Index 607
Mexico 247
Notes 285
References 286
v
PREFACE
This book traces lineages, assemblages, and events in the I began my work at Harvard University in 1963 under a post¬
history of Latin American vegetation and terrestrial paleoenvi- doctoral fellowship generously supported through the Gray
ronments from just prior to the asteroid impact at the end of Herbarium and its director, Reed C. Rollins. The first field trip
the Cretaceous through the turbulent times of the Holocene. of the project was during Christmas of 1963-64 to collect fos¬
It is a continuation of Fate Cretaceous and Cenogoic History of sil wood for the Hankins Collection (Preface Figs. 1, 2, 3) and
North American Vegetation (north of Mexico) (Graham, 1999a), Tertiary sediments of several ages from cores of the Panama
which includes discussions of Cause and Effect (Climate, Plate Canal Company. The Chief Geologists of the company, Rob¬
Tectonics, Catastrophes); Context (Global Marine Paleotem¬ ert Stewart and later his wife, Jay Stewart, contributed much
perature Curve, Sea-Level Curve); and Methods, Principles, helpful information throughout the Panama studies. Samples
Strengths, and Limitations. Some information on climate is were collected from the Gatuncillo (late Eocene), Culebra, Cu-
reviewed here, but chapters 2, 3, and 4 of the introductory caracha, La Boca (early Miocene), and Gatun (late Miocene)
volume should be consulted as needed for background to the formations.
present text. To minimize repetitious citation, it is referenced The Christmas season was often unsettled in Panama, with
here as I: (page number, chapter, or figure) where topics rel¬ demonstrations orchestrated to coincide with negotiations for
evant to this volume are discussed. a new lease agreement for the Panama Canal. Those in 1963
were worse than usual (Preface Fig. 4), and the months follow¬
BEGINNINGS AND ACKNOWLEDGMENTS
ing were not a prudent time for fieldwork in Panama. Also,
study of the fossil material was proving difficult because of the
My studies in Neotropical vegetation history began in 1963
relatively small reference collection of about 5000 slides and
when Elso Barghoorn of Harvard University called my dis¬
the few general summaries available on the modern communi¬
sertation adviser Chester Arnold at the University of Michi¬
ties, their composition, distribution, and ecology. Meanwhile,
gan to ask if any students there were familiar with Miocene
samples had been obtained from the middle Oligocene San
palynofloras and interested in working on an assemblage of
Sebastian Formation of Puerto Rico through the cooperation
that age from Panama. I had just completed a study of the
of Reginald Briggs and Othmar Tobisch (U.S. Geological Sur¬
Miocene Succor Creek and Trout Creek floras of Oregon,
vey, San Juan). The extant vegetation of the Antilles was com¬
and Professor Barghoorn had recently obtained samples from
paratively well known from the work of Richard Howard and
the Panama Canal Company, used by Alexandra Bartlett for
others. The National Science Foundation began supporting my
her doctoral research on Quaternary climates and sea-level
studies on the Tertiary vegetation and paleoenvironments of
changes in Panama (Bartlett & Barghoorn, 1973). These sam¬
Latin America in 1967 under the project, “Studies in Neotropi¬
ples extended into the underlying Miocene Gatun Formation.
cal Paleobotany,” and the San Sebastian fossil flora was the
first published in that series (Graham & Jarzen, 1969). The
second was on the middle Pliocene Paraje Solo flora near Co-
atzacoalcos, Veracruz, Mexico (Graham, 1976). The Mexican
project was facilitated through introductions by Arturo Go-
mez-Pompa (UC MENUS, Riverside, California) to Agustin
Ayala-Castaiiares (UNAM) and Guillermo P. Salas (UNAM,
PEMEX), who provided locality data and access to PEMEX
sites in southeastern Mexico. Field associates in Mexico were
students Enrique Martinez-Hernandez (now at the Instituto
Geologia, UNAM) and David Jarzen (Florida Museum of
Natural History). Arturo Gomez-Pompa accompanied me
on a field trip to Veracruz that included study of the cloud
forest, which proved valuable in interpreting the Paraje Solo
vegetation.
The third project, initiated in 1980, was to be on Neogene
Preface Figure 1. Frank Hankins (left) and Elso Barghoorn ex¬
palynofloras from Guatemala. Political unrest made it impos¬
amining a piece of petrified wood for which the area around David,
sible to do the fieldwork, but in the meantime things had
Panama, is famous. Hankins was an avid collector of petrified wood
and his extensive collections are now at Harvard University. settled down in Panama. Also, the Flora of Panama (Woodson
VI
Preface vii
et al., 1943 et seq.; D’Arcy, 1987a, b; D’Arcy & Correa A.,
1985) was nearing completion, the Flora of Barro Colorado Island
(Croat, 1978) was available, and it was possible to conclude the
Panama project in 1991 (Graham, 1985,1988a, b, 1989,1991a,
b, c; Graham et al., 1985). The Guatemala study was completed
18 years after it was initiated (Graham, 1998), through the co¬
operation of Gabriel Dengo (Centro Estudios Geologicos
America Central, Guatemala City) and Burke Burkart (Univer¬
sity of Texas, Arlington).
Data on the vegetation history of Costa Rica came from the
middle Pliocene Uscari sequence (Graham, 1987) and from the
Pliocene Rio Banano Formation (Graham & Dilcher, 1998).
Luis D. Gomez arranged a field trip to the Cerro de la Muerte
in the Cordillera Talamanca that provided helpful insights into Preface Figure 2. The Posada San Sebastian at David, Panama. The
the modern vegetation of Costa Rica. Another plant micro¬ entire facade of the posada is made of petrified wood. The age of the
fossil flora was recovered from the Oligo—Miocene La Quinta wood is unknown, but it is likely Neogene, possibly Miocene.
Formation of Chiapas, Mexico (Graham, 1999b), and studied
in cooperation with Rodolfo Palacios Chavez (Instituto Politec-
nico National, Mexico City; Graham & Palacios Chavez, 1996). sential in building the reference collection to its present size
Throughout the studies in Mexico, Jerzy Rzedowski provided of about 25,000 slides. Through the good offices of Director
information on the modern vegetation and other courtesies Peter Raven, I was a research associate at the Missouri Bo¬
that are sincerely appreciated. tanical Garden (MO) between 1975 and 2003, and curator of
Fossil palynofloras from the Antilles include the Mio—Plio¬ paleobotany and palynology since that time, with access to the
cene Artibonite flora from Haiti (Graham, 1990), with grate¬ expertise of the research staff and the extensive library, data¬
ful acknowledgment to Walter Judd (University of Florida, bases, and herbarium collections. The year 1969-70 was spent
Gainesville) and Dan Skean (Albion College, Albion, Michi¬ at the University of Amsterdam working on the Panama mate¬
gan); the middle Eocene Guys Hill Formation of Jamaica rial, and that visit included many valuable discussions on the
(Graham, 1993), with the collaboration of Edward Robinson paleoecology of northern South America with Thomas van
and Stephen Donovan (University of the West Indies, Kings¬ der Hammen and T. J. Wijmstra. Another visit was made to
ton, Jamaica); and the middle Eocene Saramaguacan flora of Panama in 1990 to the Smithsonian Tropical Research Institute
Cuba (Graham et al., 2000), co-authored with student Duane (STRI) as part of its Senior Visiting Scholars Program through
Cozadd, Alberto Areces-Mallea (San Juan, Puerto Rico), and the courtesy of David Roubik.
Norman Frederiksen (U.S. Geological Survey, Reston, Vir¬ Shirley A. Graham has taken many of the photographs,
ginia). These studies have also benefited from discussions on reviewed most of the manuscripts, and has been a field associ¬
Antillean geology with Paul Mann (Institute for Geophysics, ate throughout the project, in addition to pursuing her own
University of Texas, Austin), James Pindell (Tectonic Analysis, research on the taxonomy of the Lythraceae. Her efforts are
Ltd., West Burton, U.K.), and Manuel Iturralde-Vinent (Museo sincerely appreciated and deserve special acknowledgment.
Nacional de Historia Natural, Havana, Cuba). Others providing field and technical assistance, informa¬
The South American studies began with an invitation from tion, photographs, literature, reviews, and/or permission to
Omar Colmenares (Centro Investigacion Desarrolo Filial use published and unpublished material are Sandra Arango-
Petroleos Venezuela, INTEVEP) to consult on an Eocene Caro, Paul Baker, Viviana Barreda, Mike Blomberg, William
section from the Maracaibo Basin. Another study was on a Buck, Robyn Burnham, Mark Bush, Taciana Cavalcanti, Paul
Mho—Pliocene flora from the Eastern Cordillera of the Boliv¬ Colinvaux, Laurel Collins, Trisha Consiglio, Mireya Correa,
ian Andes (Graham et al., 2001), supported by the National Georgina Del Fueyo, Thomas Donnelly, Grenville Draper, Is¬
Geographic Society and co-authored with Kathryn Gregory- mael Ferrusquia-Villafranca, Julio Figueroa, Michael Grayum,
Wodzicki (Lamont-Doherty Earth Observatory) and student Barry Hammel, Henry Hooghiemstra, Sally Horn, Trevor Jack-
Kari Wright. Michael Nee (NY) accompanied me on a field son, Carlos Jaramillo, Ivan Jimenez, David Lea, Barbara Ley¬
trip to the cloud forests of Bolivia, and further information on den, Lucia Lohmann, Maria Socorro Lozano-Garcia, Michael
the modern vegetation was provided by Peter Jorgensen and Macphail, Steven Manchester, Enrique Martinez-Hernandez,
James Solomon (MO). Sarah Metcalfe, Barbara Mohr, Olga Martha Montiel, Scott
Other individuals have given valuable assistance in a variety Mori, Kevin Nixon, Anthony Orme, E. G. Ottone, Dolores
of ways throughout the study. In particular, access to spore Piperno, Jay Quade, Susanne Renner, Andrea Schwarzbach,
and pollen herbarium material was made possible through Da¬ Alan Smith, Mario Sousa S., W Douglas Stevens, Donald
vid Lellinger, Joan Nowicke, and Stanwyn Shetler (US); Patricia Stone, Charlotte Taylor, Alice Tryon, Rolla Tryon, Carmen
Holmgren (NY); and Nancy Morin (MO). This access was es- Ulloa Ulloa, Thomas Van Devender, Bruno M. T. Walter,
viii Late Cretaceous and Cenozoic History of Latin American Vegetation and Terrestrial Environments
tions of fieldwork. Two examples are given here to illustrate
why so many people initially drawn to Latin America choose to
spend their careers studying the natural history of the region.
In August 1965, we were searching for a locality along the path
between Atotonilco and Metquititlan, Hidalgo, Mexico. Our
truck slipped off the road into a deep hole in front of a culvert
that funneled water from the nearby mountains into a canyon
below. It started to rain, giving every indication that the truck
would be swept into the canyon. It was getting dark, and a
man offered to walk with us into the nearest village about 5
km away, where the local teacher of English made arrange¬
ments for accommodations and for help in digging the truck
out the following morning. It rained off and on throughout
the night, and although not heavy, it resounded ominously on
Preface Figure 3. Courtyard of the Posada San Sebastian. The eggs
the tin roof and gave visions of National Science Foundation’s
were placed among the plants prior to our arrival to deflect glances of
truck careening down the canyon in a torrent of water. We
those suspected of having “the evil eye.”
got the truck out, and the letter written by the teacher, Ma¬
ria del Carmen, remains a valued reminder of the experience
Reinhard Weber, Tom Wendt, and the many other persons (frontispiece).
acknowledged with gratitude in the primary publications. Op¬ An episode that provided some much-needed levity oc¬
portunity for exchange of information on the biology and ge¬ curred in 1962 while we were camping in a trailer park in Gua¬
ology of the Antilles was made possible through the NESCent dalajara, Mexico. We were tenting and during rainy nights slept
Conference, Biological Diversification on the West Indian in the car. The accommodations were beginning to lose their
Archipelago (Punta Cana, Domican Republic, 5—9 July 2006). magic, when there pulled into the park a vehicle that made
The book benefited considerably from the editorial talents of ours seem luxurious. It was a large yellow school bus that had
Eileen P. Duggan, Allison Brock, Beth Parada, and Victoria C. a hole cut in the roof, and mounted on top was the body of a
Hollowell, scientific editor of the Missouri Botanical Garden Nash Rambler serving as an observation deck. It looked like
Press. Sources of photographs and copyright holders granting a bizarre accident, but the American family of five seemed to
permission to use illustrations are listed in the legends. In a enjoy the attention and were having a grand time.
very few instances, it has proven impossible to reach a pub¬ The information presented in this text represents a synthe¬
lisher, author, and/or estate for permission after best-intent sis of nearly 50 years of study and fascination with the history,
efforts. These are indicated in the legends with the source of culture, and vegetation of Latin America. My deep apprecia¬
the illustration and the author provided. All uncredited photo¬ tion goes to the supporting foundations, institutions, corpora¬
graphs and illustrations are by the author. tions, and the many colleagues who have made it possible.
The publications cited above are only a small part of the ex¬
tensive literature on Latin American vegetation and vegetation REFERENCES
history contributed over a span of 150 years by both foreign
and resident scientists. The perseverance and dedication of the Bartlett, A. S. and E. S. Barghoorn. 1973. Phytogeographic his¬
early workers in the American tropics warrant special admira¬ tory of the Isthmus of Panama during the past 12,000
tion and respect—e.g., Arana, Bates (Clodd, 1892); Cabral, de years (A history of vegetation, climate, and sea-level
Aguirre, de Orellana, de Teixeira, the Godins, Wickman, and change). In: A. Graham (ed.), Vegetation and Vegetational
others (Smith, 1990); Darwin, La Condamine, Spruce, von History of Northern Latin America. Elsevier Science
Humboldt (von Hagen, 1945; Seaward & Fitzgerald, 1996); Publishers, Amsterdam, pp. 203—299.
Palmer (McVaugh, 1956); Pringle (Davis, 1936); Wallace (Knapp, Berry, A. (ed.). 2002. Infinite Tropics: An Alfred Russel Wal¬
1999; Raby, 2001; Berry, 2002; Camerini, 2002; Shermer, 2002); lace Anthology. Verso, London.
Ruiz and Pavon (Steele, 1964), and others. Excerpts from the Camerini, J. R. (ed.). 2002. The Alfred Russel Wallace Reader:
writings of these early authors are reprinted in Chazdon and A Selection of Writings from the Field. The Johns Hop¬
Whitmore (2002). The fieldwork of numerous early geologists kins University Press, Baltimore.
and paleobotanists such as V. Auer, E. W Berry, E. Dolianiti, Chazdon, R. L. and T. C. Whitmore. 2002. Foundations of
J. Felix, J. Frenguelh, A. Hollick, E. P. Oliveira, F. W Sommer, Tropical Forest Biology. University of Chicago Press,
and others was equally arduous, and their contributions are ac¬ Chicago.
knowledged at appropriate places in the text. Clodd, E. 1892. Bates’ River Amazons: The Naturalist on the
All who have been privileged to work in Latin America are River Amazons. John Murray, London.
aware of the legendary courtesies of colleagues, and the inevi¬ Croat, T. B. 1978. Flora of Barro Colorado Island. Stanford
table experiences that can alleviate the difficulties and frustra¬ University Press, Stanford, CA.
Preface IX
D’Arcy, W G. 1987a. Flora of Panama, Checklist and Index.
Part I. The Introduction and Checklist. Monogr. Syst. Bot.
Missouri Bot. Gard. 17.
-. 1987b. Flora of Panama, Checklist and Index. Part II.
Index. Monogr. Syst. Bot. Missouri Bot. Gard. 18.
-and M. D. Correa A. 1985. The Botany and Natural
History of Panama: La Botanica e Historia Natural de
Panama. Missouri Botanical Garden, St. Louis.
Davis, H. B. 1936. Life and Work of Cyrus Guernsey Pringle.
University of Vermont, Burlington.
Graham, A. 1976. Studies in neotropical paleobotany. II. The
Miocene communities of Veracruz, Mexico. Ann. Mis¬
souri Bot. Gard. 63: 787—842.
-. 1985. Studies in neotropical paleobotany. IV. The Eo¬
cene communities of Panama. Ann. Missouri Bot. Gard. Preface Figure 4. Rioted Pan American Building, Panama City,
72: 504-534. Panama, seen from the grounds of the former Tivoli Hotel, Canal
region, December 1963.
-. 1987. Miocene communities and paleoenvironments
of southern Costa Rica. Amer. J. Bot. 74: 1501—1518.
-. 1988a. Studies in neotropical paleobotany. V. The University Press, Oxford, U.K.
lower Miocene communities of Panama—the Culebra -. 1999b. Studies in neotropical paleobotany. XIII. An
Formation. Ann. Missouri Bot. Gard. 75: 1440—1466. Oligo—Miocene palynoflora from Simojovel (Chiapas,
-. 1988b. Studies in neotropical paleobotany. VI. The Mexico). Amer. J. Bot. 86: 17—31.
lower Miocene communities of Panama—the Cucaracha -, D. Cozadd, A. Areces-Mallea, and N. O. Frederiksen.
Formation. Ann. Missouri Bot. Gard. 75: 1467—1479. 2000. Studies in neotropical paleobotany. XIV. A palyno¬
-. 1989. Studies in neotropical paleobotany. VII. The flora from the middle Eocene Saramaguacan Formation
lower Miocene communities of Panama—the La Boca of Cuba. Amer. J. Bot. 87: 1526-1539.
Formation. Ann. Missouri Bot. Gard. 76: 50—66. -and D. L. Dilcher. 1998. Studies in neotropical paleo¬
-. 1990. Late Tertiary micro fossil flora from the Repub¬ botany. XII. A palynoflora from the Pliocene Rio Banano
lic of Haiti. Amer. J. Bot. 77: 911—926. Formation of Costa Rica and the Neogene vegetation of
-. 1991a. Studies in neotropical paleobotany. VIII. The Mesoamerica. Amer. J. Bot. 85: 1426-1438.
Pliocene communities of Panama—introduction and -, K. M. Gregory-Wodzicki, and K. L. Wright. 2001.
ferns, gymnosperms, angiosperms (monocots). Ann. Mis¬ Studies in neotropical paleobotany. XV. A Mio-Pliocene
souri Bot. Gard. 78: 190-200. palynoflora from the Eastern Cordillera, Bolivia: Implica¬
-. 1991b. Studies in neotropical paleobotany. IX. The tions for the uplift history of the Central Andes. Amer. J.
Pliocene communities of Panama—angiosperms (dicots). Bot. 88: 1545-1557.
Ann. Missouri Bot. Gard. 78: 201—223. -and D. M. Jarzen. 1969. Studies in neotropical paleo¬
-. 1991c. Studies in neotropical paleobotany. X. The botany. I. The Oligocene communities of Puerto Rico.
Pliocene communities of Panama—composition, nu¬ Ann. Missouri Bot. Gard. 56: 308-357.
merical representations, and paleocommunity-paleoenvi- -and R. Palacios Chavez. 1996. Additions and prelimi¬
ronmental reconstructions. Ann. Missouri Bot. Gard. 78: nary study of an Oligo-Miocene palynoflora from Chi¬
465-475. apas, Mexico. Rheedea 6: 1-12.
-. 1993. Contribution toward a Tertiary palynostratig- -, R. H. Stewart, and J. L. Stewart. 1985. Studies in neo¬
raphy for Jamaica: The status of Tertiary paleobotanical tropical paleobotany. III. The Tertiary communities of
studies in northern Latin America and preliminary analysis Panama—geology of the pollen-bearing sediments. Ann.
of the Guys Hill Member (Chapelton Formation, middle Missouri Bot. Gard. 72: 485-503.
Eocene) of Jamaica. In: R. M. Wright and E. Robinson Knapp, S. 1999. Footsteps in the Forest: Alfred Russel Wallace
(eds.), Bio stratigraphy of Jamaica. Geol. Soc. Amer. Mem. in the Amazon. The Natural History Museum, London.
182: 443-461. McVaugh, R. 1956. Edward Palmer: Plant Explorer of the
-. 1998. Studies in neotropical paleobotany. XI. Late American West. University of Oklahoma Press, Norman.
Tertiary vegetation and environments of southeastern Raby, P. 2001. Alfred Russel Wallace: A Life. Princeton Univer¬
Guatemala: Palynofloras from the Mio-Pliocene Padre sity Press, Princeton, NJ.
Miguel Group and the Pliocene Herreria Formation. Seaward, M. R. D. and S. M. D. Fitzgerald (eds.). 1996. Richard
Amer. J. Bot. 85: 1409-1425. Spruce (1817-1893): Botanist and Explorer. Royal Bo¬
-. 1999a. Late Cretaceous and Cenozoic History of tanic Gardens, Kew, Richmond, U.K.
North American Vegetation (north of Mexico). Oxford Shermer, M. 2002. In Darwin’s Shadow: The Life and Science
X Late Cretaceous and Cenozoic History of Latin American Vegetation and Terrestrial Environments
of Alfred Russel Wallace. A Biographical Study on the Press, Durham, NC.
Psychology of History. Oxford University Press, Oxford, von Hagen, V. W 1945. South America Called Them: Explora¬
U.K. tions of the Great Naturalists La Condamine, Humboldt,
Smith, A. 1990. Explorers of the Amazon. University of Chi¬ Darwin, Spruce. Alfred A. Knopf, New York.
cago Press, Chicago. Woodson, R. E., Jr., R. W Schery, and collaborators. 1943 et
Steele, A. R. 1964. Flowers for the King: The Expedition of seq. Flora of Panama. Ann. Missouri Bot. Gard., vol. 30
Ruiz and Pavon and the Flora of Peru. Duke University et seq.
PROLOGUE
The tropical regions of the Earth contain the greatest con¬ extend over time, such as the origin and spread of lineages
centration of organisms and communities of organisms on the and communities; the origin of the northern temperate ele¬
planet. Understanding their origin, diversification, migration, ment within the Latin American biota; and the climatic and
current status, and value in the broadest sense and developing biotic consequences of the rise of the Andes Mountains, the
workable policies of conservation and sustainable develop¬ opening of the Drake Passage between Antarctica and South
ment constitute some of the most challenging problems ever America, and the closure of the Isthmus of Panama. Another
to face humankind (Achard et al., 2002; Balmford et al., 2002; consideration in formatting the coverage was to select topics
Leshner, 2002; Mann, 2002; Raven, 2002). Fortunately, this is and develop a sequence of presentations that would provide
a time when a vast array of methodologies are available for in¬ a logical unfolding of a complicated history for both special¬
vestigating tropical biotas and the environments in which they ists and the general reader. The companion volume on North
evolved. It is almost routine to accept that we can now deter¬ America has been used for upper-division undergraduate and
mine the C09 concentration of the Earth’s atmosphere over graduate-level courses and seminars, and the present text has
the past 100 million years; reconstruct temperatures through been designed for the same purpose. To achieve the goal of
eons of geologic time as changes in the Earth’s position rela¬ reference manual and a general text, many of the data and sup¬
tive to the sun determine the amount, and alterations in ocean porting details are presented in tables and placed in appendices
and atmospheric currents determine the distribution, of heat at the end of the book. There is a detailed subject index, and
and cold; detect fluctuations in ancient ozone levels from the a section on General Readings with updates is included in the
amounts of DNA-protecting pigments in Lycopodium spores References at the end of each chapter.
(Lomax cited in Morton, 2005); trace patterns of precipitation The survey begins with background summaries on the
from mite floras preserved in stalagmites; estimate how high geography (Chapter I), geology (Chapter 2), and vegetation
mountains were at different stages in their history; follow cy¬ (Chapter 3). The geographic definition of the region is com¬
cles of drought from the titanium content of basin sediments; paratively straightforward—it is Latin America and it extends
relate these cycles to the rise and fall of the great ceremonial from about 32°N, south across the Tropic of Cancer at 23.5°N
centers of Latin America; determine how long El Ninos and and the Tropic of Capricorn at 23.5°S (the geographic tropics),
La Ninas have perturbated global climates; assign absolute ages to about 55°S. A more formal definition of Latin America as
to these events based on 10Be and other isotopes; and compare a political region is given in Chapter I. This coverage provides
the appearance of lineages in the fossil record with divergence reference points and place names for geologic features, vegeta¬
times and evolutionary patterns based on combined morpho¬ tion types, and fossil localities mentioned in the text, and it fol¬
logical and multiple-gene phylogenies. These are remarkable lows the organization of the earlier volume on North America
achievements, and it is an exciting time to be investigating pat¬ north of Mexico. There are several useful Web sites for addi¬
terns, processes, cycles, and events of global and extraterres¬ tional geographic information on Latin America. These change
trial origin that have interacted with the biota to produce some frequently, but among those operational at the time of writing
of the Earth’s most complicated ecosystems. are http://earth.google.com (allows tilting of aerial view relief
The telling of this history presents formidable problems maps [DEM—Digital Elevation Models] to give topographic
of synthesis and organization, and many different paths could profiles), http://earfh-info.nima.mil/gns/html, and http://wwwsasi.
be followed. The one taken here traces the history of Latin group.shef.ac.uk/worldmapper/index.html.
American vegetation and terrestrial paleoenvironments from It is less easy to set a suitable time span for the geologic
the Late Cretaceous through the Cenozoic, identifies the con¬ review, but the one emphasized here begins in the Late Cre¬
catenation of causal factors involved in the modernization of taceous, about 70 Ma, when (I) the modern angiosperm flora
the vegetation, appraises the reconstructed history in the con¬ had ecologically diversified and was established over much of
text of results from independent lines of inquiry, describes the globe (Coiffard et al., 2007; Heimhofer et al., 2007), (2)
methods, emphasizes the broader value or “so-whatness” many taxa were modern enough in aspect to allow identifica¬
of the information, and provides a guide to the literature to tion of the fossils to the family and generic level, and (3) an
facilitate further study and encourage independent assess¬ increasing number of organisms were associated in plant for¬
ments. The traditional approaches are either stratigraphic (viz., mations sufficiently similar to extant ones to allow estimates of
by time intervals) or geographic (by country or region). The the paleoenvironment.
principal disadvantage to both is that they compartmentalize Just as the Late Cretaceous encompasses a watershed bio¬
the subject into discrete segments. This complicates treating logical event in the rise to dominance of the angiosperms, it
events that involve more than one region and processes that is also immediately prior to the asteroid impact at Chicxulub
XI