Thursday, December 22, 2016

Timely quotes about science: Science Rules

Hi there! Greetings from the blog-verse. Here I share some interesting, inspirational, and timely quotes about science from some of the greatest minds of our time. Enjoy and remember the wisdom of these wise men.



"Change will come slowly, across generations, because old beliefs die hard even when demonstrably false"  E. O. Wilson

"We are drowning in information while starving for wisdom. The world henceforth will be run by synthesizers, people able to put together the right information at the right time, think critically about it, and make important choices wisely"  E. O. Wilson

"Political ideology can corrupt the mind and science" E. O. Wilson


"There is no greater education than the one that is self-driven" Neil deGrasse Tyson


"Science simply tells the best stories" Neil deGrasse Tyson

"When you make the finding yourself even if you're the last person on Earth to see the light, you'll never forget it" Carl Sagan


"Science rules" Bill Nye



Tuesday, November 1, 2016

Public Connotation : Theory or Hypothesis?


Most people do not know the difference between a theory and a hypothesis. These two terms hold different connotations and meaning for the public than does for scientists--or at least science trained. 

Page from Charles Darwin's diary
 (courtesy of Darwin Online).
In science, a theory is a well-supported fact. It is supported and corroborated by many tests or experiments and observations. Examples of theories in science include the theory of evolution in Biology, the theory of plate tectonics, theory of gravitation, the theory of Relativity, and the laws of photoelectric effects(which by the way is one of Einstein's greatest contribution to science which gained him the Nobel Prize in theoretical physics in 1921, but I digress). These theories are not conjecture and are considered facts because they have been proven over and over again, consistently, and are in a way, predictable. No serious person, in my opinion, doubts gravity. 

A scientific hypothesis is a question or idea that remains to be proven--meaning it is not yet quite a theory or law; more observations and experimentation is needed to corroborate it or disprove it. For example, the hypothesis that dinosaurs were warm-blooded, or whether natural selection is the main mechanisms of speciation--the source or origin of species, or the currently hot hypothesis of human-induced climate change. These are scientific hypotheses. 

An important aspect of hypotheses is that they must make testable predictions. If a hypothesis does not make a prediction or gives it certain qualities that allow the researcher to test it, then the hypothesis make the logical fallacy of being empty. An empty hypothesis thus makes no prediction and is untestable. One could never know whether is true or conjecture and would have to speculate always on its foundation. An example of this is that of the Bermuda Triangle, but that's for another post. These are the meaning of a scientific theory and hypothesis as intended.

The public, however, uses the term theory with another meaning. For instance, the theory that Big Foot exists, or the theory of Kennedy's assassination, or even of ancient aliens, gave rise to our most important civilizations. These in reality, if there is any serious intention, are only hypotheses. They still require much more convincing evidence in order to be proven or disproven. But they are by no means theories or laws, they are still hypotheses.

So there, the public confuses the meaning of the terms hypothesis and theory. You may hear it on the news or read it on social media. But these vehicles only seem to obscure and contort the meaning of these two terms, which results in a confused usage by the public, leading to the misusage of the term theory when is really meant hypothesis.

Famous Charles Darwin "I Think" quote.
Charles Darwin diary courtesy of Darwin Online

I recommend, although in my very own biased way, two books that can expand on these topics, and help in our ever-continuous battle against science illiteracy in the World. One is "Unscientific America: How Scientific Illiteracy Threatens our Future" (2010) by Chris Mooney and Sheril Kirshenbaum, Basics Books, New York. The second is Donald Prothero's (2007) "Evolution: What the Fossils Say and Why it Matters" Columbia University Press, New York. 


Tuesday, October 11, 2016

Columbus and Rediscovery of the New World

In October we celebrate Christopher Columbus rediscovery of the New World.

On October 11, 1492, Rodrigo de Triana shouted "land!" from the mast of the Santa Maria. The next morning, on the island of Guanahani, modern Bahamas, Columbus and his crew began an unprecedented conquest of the Americas that involved the extinction of thousands of species and the introduction of many others.

Engraving from 1496 showing explorers on their way to the New World. 

The most expensive, and even outrageous human enterprises have been military in nature. Science usually tags alongside such enterprises, but not riding shotgun. Columbus's exploration was funded by the interest of the Spanish sovereigns in search of new riches and a military position that could compete with the growing powers of Portugal and England. And although it brought map makers (cartographers), cosmographers and geographers, scientific interest was low in his first voyages. 

It was only after that science extended its arms outwards, alongside colonization. Soon after the rediscovery--and I continue to use the term rediscovery because humans had already discovered the American continent some 15,000 years before, and northern Europeans 1000 years earlier--native Amerindians succumbed to the new colonist's diseases, enslavement and weapons. Unfortunately, the science that came along was opportunistic and cast a heavy weight on the existence of many native species with scant documentation.

The first colonists had to eat off the land, and in many cases brought with them animals that soon became feral where they did not evolve or were not suited for ecologically, driving other native species to extinction.

Native fruit plants from an engraving in Benzoni's Historia del Mondo Novo (1563).

An interesting case is that told by father Bartolome de la Casas. In 1512, during the official exploration and conquest of Cuba by Diego Velazquez, he and is crew killed and ate thousands of Cuban macaws (Ara cubensis) in Casaharta, a town in central-northern Cuba.
The Cuban macaw has been extinct in Cuba since the 19th century but had been rare since the 18th century, when deforestation and overhunting for its beautiful feathers drove it to rarity, and later extinction. In the mid 19th century, the german naturalist Johannes Gundlach found it in the Zapata Swamp, southwestern Cuba.
A similar case has occurred to the Cuban crows (Corvus minutus and Corvus nasicus), and the Cuban ivorybill woodpecker (Campephilus principalis) to name a few.  These species had survived at least a million years of climate change, and over 5000 years of Amerindian coexistence, to become extinct during the colonization (see some of my own research on this here).




But the scientifically inclined explorers served well by documenting what they could about the lush natural richness of the Americas. Among them, Peter Martyr, a geographer, was the first historian of the New World. Others such as the Spanish Oviedo and the Italian Benzoni included detailed accounts of the native species found in the American Eden. Plants, animals, and even cryptic mythological creatures were initially described, such as the manati, a water mammal though to be a siren. Its scientific mammalian order--Sirenia--carries the idiosyncrasies of the era that brought it--through science--to world knowledge.

Engraving of a manati, a sirenian marine mammal as described by Oviedo in his
Historia General de las Indias (1547).


Monday, August 8, 2016

Progressus: A project for Cuban Archaeology




Several months ago I expressed my excitement in becoming part of the archeological project Progressus. Since then, I have collaborated with Odlanyer Hernandez, Boris Rodriguez, Cristian de la Rosa, Leonel P. Orozco, Jorge Garcell, and Ricardo A. Viera (to name a few); all Cuban archeologists and historians at the front of archaeological research, and concerned with the integration of archaeological and historical data in the rescue and preservation of Cuban cultural heritage.

Since then, Ricardo Viera and I have written two small notes on several aspects of Matanzas history and archaeology. One is dedicated to the bombardment of the city of Matanzas 27 April 1898. This was the first bellic act of the Spanish-Cuba-American war soon after the USS Maine blew in the bay of Havana on February 15 of that same year. The other pertains to our research on the archaeology of clay tobacco pipes excavated from fort Castillo de San Severino and published in the International Journal of Historical Archaeology, aforementioned here.

Some of our colleagues and members of Progressus mentioned above contributed greatly to this research since many of them have published extensively on the fort's archaeology. It is my pleasure to be able to contribute to their great body of research and to be part of their team. Moreover, there are plans of making Progressus a great venue for international collaboration, including Argentinean, Swedish, Cuba, and American researchers to deepen our understanding of Cuban historical archaeology.

Please visit Progressus blog here to meet our colleagues, and to stay informed on our work, contributions, and future plans. There you will find articles, photographs, and articles on battlefields, fortifications, and artifacts related to the local history of Matanzas, Cuba. There are surely interesting findings down the pike, as we continue to unravel our common history.

Stay tuned for more news!




Tuesday, July 26, 2016

The living cave floor: intro to cave faunas

E. A. Martell, one of the first professional cave explorers, expressed in 1894 that "caverns and abysses are natural laboratories ready for numerous and curious researchers".

Those who visit caves frequently notice that some caves are alive! Walk into a cave room and with a swipe of the lantern you see the cave floor move! - Seems like something out of a horror film, but caves are truly alive.

Cave roaches of the family Polyphagidae, scavengers of the guano cave floors. This is an example of a guanophile troglobites. 

Caves are alive because they are teeming with life. From the microscopic viruses and bacteria to the much more complex bats, and even humans, caves provide a subterranean environment that is both beautiful and mysterious, resulting in the specialization of extraordinary organisms.

American roach Periplaneta americana (Blattidae) another common cave scavenger. 

The subterranean world is a complex environment. In caves, light enters unevenly. The deepest rooms, those farthest away from the entrance are the darkest if no other source of light exists. But even in such absence of light, organisms proliferate and evolve. These cave organisms can be defined or grouped depending on their cave habitat and preferences. Each has its own niche.

Troglobites are organisms that are strict cave dwellers, and complete their life cycles deep inside caves. Troglophiles are occasional cave dwellers. They do not complete their life cycle inside the cave, but they could if needed or preferred. They can be facultative cave inhabitants.

Trogloxenes, on the other hand, are similar to troglophiles in that they too are facultative cave dwellers, but their life cycles always require they leave the cave, surfacing to eat or reproduce. In this case, most organisms that people associate with cave dwelling are readily trogloxenes. Bats, birds like oil birds, owls, swallows, some reptiles, amphibians, and several species of insects, are all trogloxenes.

Cavernicolan glowworm in a cave in the Dominican Republic. Photographs courtesy of Adrian Tejedor. This is the larval state of a trogloxene arthropod. It is bioluminescent and truly interesting to observe. 

Other cave organisms are strictly aquatic cave dwellers. These are called stygobites, for they can only live in cave ponds or lakes. The blind fish and arthropods that live in vadose water lakes found within deep parts of a cave system represent this group. These organisms are very specialized. They have adapted to the dark aquatic environments and have lost their eyesights, color pigmentation, or eyes altogether.

There are organisms that can be considered accidentals because they enter caves by falling in, or because they are momentarily attracted by food or shelter inside. These include several mammals such as rodents and carnivores, birds, reptiles, amphibians, and many arthropods. Troglodyte is a term reserved for humans who use caves as a home or shelter. Humans have been using caves since the paleolithic, nearly a million years ago!

A carcass of a Cuban fruit-eating bat Artibeus jamaicensis eaten by
cave roaches of the family Polyphagidae: scavengers or the cave floor.
Cueva de Los Nesofontes, Mayabeque, Cuba 2003.

Caves not only provide secluded microclimates but microhabitats that are richly ecologically stratified and interconnected. An example is illustrated by numerous species of different bacteria and arthropods, that as an adaptation, live off the bat droppings (or guano) deposited in cave floors. These are known as guanophiles and are often troglobitic arthropods.


Plants growing from seeds brought in the excrement
of fruit bats A. jamaicensis. The Dominican Republic, 2004.

Trogloxenes often serve as the food of troglobites. Many are scavengers that feed on decomposing matter brought in by other organisms, such as seeds brought in by fruit bats, or the dying bats themselves, as is the case of the Cuban fruit bat Artibeus jamaicensis carcass devoured by cave-floor roaches in a cave in Cuba shown above.
Many of these organisms are agents of bone accumulations and dispersion within caves, a micro-field within taphonomy that I am most interested in. See my previous ruminations on this previous post.

Decomposed and guano-buried funnel-eared bat Natalus major eaten by small cave-floor ticks genus Pantricola (?). Los Haitises, the Dominican Republic, 2004.

A wide variety of organisms has evolved in caves. These are characterized by intricate specializations such as staged reproduction cycles, feeding mechanisms, or sensitivities to light that allows them to exist only in the intricate microclimates-ecosystems found in the subterranean world. Such diversity and these special characteristics have been naturally selected over millennia depending on the distribution of these organisms and the niches they inhabit withing the geography of a cave.

Cave lake in the interior of Feather's Cave, Matanzas, Cuba.This lake used to have blind fish of the genus Lucifuga

Most of troglobites and trogloxenes are relics of the past. Some of the aquatic stygofauna are descendants of freshwater, intertidal, or marine organisms that became trapped in a cave pools and lakes, becoming isolated there. Most of them evolved from exterior faunas that adapted to the cave conditions after isolation.

Cuban boa Chilabrothus angulifer on the hunt for fruit bats. Nesofonte's Cave, Mayabeque, Cuba. This species is a trogloxene that uses caves as a refuge, for feeding and reproduction. These reptiles have adapted to hang from the walls and catch flying bats. 

Exterior faunas enter caves with inflowing rivers, floodwaters, and groundwaters that invade, actively or passively, cave environments. Others become trapped or fall in accidentally as mentioned before. More so, streams and rivers can carry inside sediment and plant debris often carrying organisms from the exterior into the cave. These organisms then become underground colonizers, evolving in isolation from their exterior populations. The cave itself being the barrier to their gene flow.

Cave gours or pools from Bellamar's Cave, in Matanzas. Some of the green and red films that can be seen represent cyanobacteria that live off the chemicals of the rocks and the dim light that is artificially provided by the tour lamps (they are photosynthetic, thus needing light). 

But caves are sensitive environments and even the most minute changes can alter their microhabitats. Alterations to these delicate subterranean environments include hoards of people using caves as a tourist attraction, or "collecting" their endemic faunas or crystal formations, often downgrading their natural beauty. Or affecting their natural flora and fauna, thus affecting the natural cycles that occur within caves. Cave microenvironments are also sensitive to overall climate change, and rising sea levels. The former have the potential to drown existing habitats, and thus pushing many cave endemics to extinction or habitat fragmentation.

The isolation of subterranean environments makes cave faunas interesting subjects to the study of evolutionary pathways, genetics, biogeography, and even virology (-the Ebola and Zaire viruses seem to have evolved in African cave environments-). Some biologists consider caves even as islands, isolated natural laboratories for evolution and natural selection. 

I think Martell was right. And like him, and many other generations of cave scientists, also known as speleologists, we continue to be attracted to caves and their intricacies. We study and divulge the beauty and complexity of caves and cave systems with the hope of understanding such environments and ecosystems better, hopefully helping us protect and understand their faunas more effectively. 

I hope this post has been informative of other interesting aspects of caves since I have already covered bats, hot caves, and cave formation in my previous posts. This post is in honor of those who dedicate their time, and often health, to study caves and unraveling the mysteries of the subterranean world.

Stay tuned for more future ruminations on caves and cave faunas!



Sunday, July 17, 2016

In memoriam et causa honoris: Johannes Gundlach

The german naturalist Johannes Christoph Gundlach was born on this date in 1810. Originally from the town of Kessel (Hesse) in Germany, he lived most of his adult life in the Caribbean island of Cuba, where he became one of its most productive naturalists.

His contributions are widely encompassing from the invertebrate mollusks to the sophisticated bats, and still relevant today. Gundlach's natural curiosity and keen taxidermy technique are well appreciated and respected by Caribbean biologists and paleontologists. The specimens he collected and prepared are treasured by many museums throughout the World. Many Caribbean species carry his name in his honor.
This post is a small tribute to his life and work and a token for the inspiration he has been in my natural interests.


Johannes Gundlach was the youngest of the seven sons of Johann Gundlach and Marie Cristine Rethberg. Since a young age, the family moved to Marburg, where his father was a professor of physics and mathematics at the Phillips University.

Since young had been interested in the natural sciences. He learned the art of taxidermy or embalming animals from his brother Henry, who was a medical student. But, although Johannes is unsuccessful in his earliest studies, he excels later as a student of zoological sciences of the University of Marburg, where he received a doctorate degree in 1837.


Dr. Gundlach arrived in Cuba in 1839. He came to Cuba, along with other two important German naturalists, Edward Otto and Louis Pfeiffer. He was passing through on his way to Suriname, by invitation of a colleague. However, his colleague died, and Gundlach decided to stay in Cuba: an island he soon fell in love with.

In Cuba, he met Carlos Booth from Matanzas, who invited him to stay at his coffee state near Cardenas. Those years were very prosperous for Gundlach, and soon the Cuban countryside revealed natural jewels to him. Immediately he discovers news species of birds, bats, mollusks, and butterflies. Among these is the Cuban bumblebee hummingbird Mellisuga helenae, named in honor of Mrs. Helena Booth, and first published by the Galician Juan Lembeye in his work "Aves de la Isla de Cuba" in 1850. This is likely the most famous of his discoveries. Others include the bats Pteronotus quadridens, Phyllonycteris poeyi, Nycticeous cubanus, among many other birds, mollusks, amphibians, reptiles, and mammals. The list is indeed very long.

Whilst in residence in Cuba, Gundlach collaborated with Cuban, American, British, and German colleagues, to whom he sent specimens collected and prepared by himself. These included the already mentioned Felipe Poey, Carlos de la Torre, William Sharp, Wilhelm Peters, Dr. Lawrence, and others of revered relevance in the world of species classification and naming (taxonomy and systematics of today).


Cuban red-bellied woodpecker Melanerpes superciliaris collected by J. Gundlach near Matanzas, Cuba.


His collection grew quickly, and between 1842 and 1852 he established a small museum. Many of the specimens showcased there are preserved today in Cuban, European, and American museums.

The realization of having had the opportunity to hold specimens collected by Gundlach, still with his handwritten tag, had been a lifelong dream until recently. Visit my previous post about museum collections to find out more about this experience.

During his 50 year stay in Cuba, Gundlach published numerous articles, and at least 5 monographs dedicated to the mammals, birds, and crustaceans of Cuba. He traveled throughout the island, and also visited Puerto Rico, where he is today revered too as an important zoologist for his additional contributions there.


Tag of a Cuban red-bellied woodpecker Melanerpes superciliaris collected
by J. Gundlach.

Dr. Gundlach died on march 15 of 1896, in the city of Havana. He is buried in the Colon Cemetery. Today he is remembered for inspiring many generations of naturalists and zoologists.




The details for this post come from several sources. Most come from Gilberto Silva-Taboada (1983) Los Murcielagos de Cuba, Editorial Cientifico-Tecnico, La Habana. The others are cited in the following:

Garcia, Florentino. 1987. Las Aves de Cuba: Subespecies endemicas, vol. 2. Electron, Gente Nueva, La Habana.

Garcia Gonzalez, Armando: Gundlach, Johann Cristoph in La Web de Biografias http://www.mcnbiografias.com/app-bio/do/show?key=gundlach-johann-cristoph

Vilaró, Juan (March 1897). "Sketch of John Gundlach". Appleton's Popular Science Monthly: 691–697.

For additional information in Spanish about Carlos de la Torre and Johannes Gundlach, visit my other blog SanCarlosdeMatanzas.blogspot.com


Tuesday, May 31, 2016

The Bats of Cuba

Bats inhabit nearly every landmass on the planet, with the exception of the arctic and Antarctica, reaching their maximum diversity in the tropics. Current tallies rank bat diversity at 202 genera and over a thousand species! (Simmons, 2005).

Bats are highly specialized mammals. Not only can they truly fly (meaning powered flight), but they use echolocation to navigate and detect prey while in flight. Echolocation is a way of navigation by echoes, which bats and other mammals like dolphins emit to sense their environment and find food. Some birds, like the oilbird Steatornis caripensis, uses echolocation, but at a level we can hear. In addition to their characteristic webbed wings, their eyesight is better in the dark than ours, demystifying their bad reputation of poor eyesight.

Leach's single leaf-nosed bat Monophyllus redmani (subspecies clinedaphus) a
pollen-nectar feeder Microchiropteran common to the Greater Antilles

Chiropterans are divided into two groups: the small echolocating bats or Microchiroptera, and the non-echolocating and much larger Megachiroptera. The giant bats portrayed in movies often represent the large fruit-eating Megachiropterans. They are not all vampire bats!    

Ecologically, bats play keystone roles in the consumption of insects, distribution of plant seeds, and pollination of plants. Other bats are carnivores, also helping maintain the ecological balance of the ecosystems they inhabit.

Bats are the most diverse mammals of the Cuban archipelago representing over 75% of Cuba's mammalian fauna! Of the 34 species of mammals recorded in Cuba, 26 are bats. Currently, these 26 species are classified into six main groups including the nose-leaf bats (phyllostomids), the funnel-eared bats (natalids), the fisher bulldog bat (noctilionid), the free-tailed mastiffs (molossids), the insectivorous ghost-faced bats (mormoopids) and the vespertilionids. The majority are well distributed within the main island of Cuba, the isle of Pines, and a few of the thousand keys that make up the archipelago (Silva, 1983; Mancina, 2011, 2012).


Waterhouse's leaf-nosed bat Macrotus waterhousei
and the Cuban fig-eating bat Phyllops falcactus digitally
drawn by biologist and bat specialist Dr. Adrian Tejedor from
field sketches of specimens captured in Pinar del Rio.

The Cuban archipelago is the largest of the Antillean islands. It is located in the Antillean subzone of the Neotropics where it enjoys a warm weather and abundant rainfall most of the year. The geological formation of the Caribbean islands provided an intricate and complex mosaic of calcium-rich rocks, such as limestone, so important to cave formation and varied soils. Altogether, these variables give rise to lush vegetation, which supported by the warm climate, incites Cuba's biodiversity, especially of bats.

The Cuban archipelago, in the Caribbean basin, as seen in Google Earth.

Geologically, Cuba has been available for bat colonization since the latest Eocene (MacPhee and Iturralde, 1994). This means that there have been somewhat permanent group of islands where Cuba is located today, at least for the last 35 million years, giving ample time for bats to reach it and evolve there.
In the Pliocene - 5 million years ago - the islands had their largest subaerial extent, and thus their largest landmass increase to date (Iturralde, 2010). This was followed by the multiple landmass fluctuations experienced during the Quaternary glaciations. During the last 800,000 years, the Cuban archipelago increased and decreased in size at least 20 times, with the glacial periods decreasing sea levels, and the interglacials increasing it. This is within a range of ~20 meters from the modern standard. In effect, this had substantial effects on the formation of karstic features, such as caves, that serve some bats as roosts, affected plant distribution, and likely also the distribution and evolution of bats in the island. But most importantly, it likely played a role on the total number of species the archipelago could sustain.


A lone Cuba fruit bat Artibeus jamaicensis parvipes in roost in Cueva Ambrosio,
Varadero, alongside Amerindian cave pictographs.

During the Quaternary, Cuba, and the Bahamas acted like a single archipelago. Today that archipelago is mostly drowned by higher sea levels. Increased sea levels likely flooded potential cave roosts affecting strict cave dwellers. There are bats that have adapted not only to live in caves but also preferring hotter environments within cave systems. Caves with hotter than normal chambers are called "hot caves" because the temperature in some of its rooms increases to above 40 degrees C with a relative humidity above 90 percent. These hot environment form in chambers with restricted access, in which large colonies of the bats roost. Their body heat, perspiration, urine and droppings, all within a very restricted and poorly ventilated cave room results in the abnormal increase in room temperature and humidity. Hot cave bats include the pollen-eater Phyllonycteris poeyi and Pteronotus quadridens.

The changes in world climate during the last 2 million years, or that Quaternary epoch that we've been referring to, brought changes in rainfall, temperatures, and potential land size, therefore potentially affecting different species. However, bats were not significantly culled by the Quaternary climatic fluctuations, as far as we can tell today from the fossil record, in comparison to other mammals groups, like monkeys and sloths, which disappeared completely. Cuba lost only three species during the last glacial maximum, ~18,000 years ago, as indicated by the fossil record of Cueva El Abron, in Pinar del Rio (see Suarez and Diaz-Franco, 2003; Balseiro, 2011). Others survived until a thousand years ago or less (Orihuela, 2012; Orihuela and Tejedor, 2012, Orihuela et al, in prep).


The greater bulldog bat Noctilio leporinus. This is Cuba's largest bat. It feeds mostly on fish,
but it has been observed eating insects near street lamps.


Cuban bats, like most bats, inhabit most ecosystems where they have evolved adaptations to many forms of feeding. There are bats that eat insects, seeds, fruits, nectar, pollen, and some that feed only on blood, such as the infamous vampire bats, or fish - as the Noctilio leporinus above. In the past, there were vampire bats in Cuba. Vampire bats are locally extinct in Cuba today, but their fossil remains suggest their presence on the main island up to several hundred years ago! (Suarez, 2005; Orihuela, 2011, 2012) (see my previous post on vampire bats here).


Thomas Horsfield on the right and John Edward Grey on the left.
Both men dedicated time to collecting and describing the first Cuban bats during the XIX century.

We owe the first published account on Cuban bats to Thomas Horsfield, who sent a letter to the prestigious Zoological Journal in 1828 while he resided in Cuba. Horsfield and the British naturalist William Sharp MacLeay sent specimens to the British museum. These specimens allowed John Edward Grey to properly describe the first species in 1840 in his article "Description of some Chiroptera discovered in Cuba", published in the Annals of the Natural History, volume IV (Silva, 1983).

The Antillean fruit-eating bat Brachyphylla cavernarum and the big free-tailed bat Nyctinomops macrotis
lithographs from Grey's first description of Cuban bats. These are also the first graphic depiction of any Cuban bat.
Lithographs made by the french J. Basire in 1839. B.cavernarum here is likely B. nana but nana was not properly
described until the early XX century.

Since then, and no doubt thanks to the efforts of many naturalists such as Johannes Gundlach in the XIX century and Gilberto Silva-Taboada of the XX, among others, the knowledge on the natural history of Cuban bats grew steadily. Their research quickly demonstrated the diversity of the Cuban bat fauna. There are more species in Cuba, with species representing most of the known New World groups, than in all the North American continent!

  Parnell's mustached bat Pteronotus parnelli from Nesofontes Cave near Matanza, Cuba.

The Cuban bat fauna is surrounded in interesting stories of accidental discoveries and rediscoveries. Such as it happened to the two bat specialists, the Cuban mastozoologist G. Silva-Taboada and Karl Koopman of the American Musem of Natural History (NY) while mistnetting bats in the Pan de Guajaibon, Pinar del Rio, in the 1950s. There they caught a living Cuban pallid bat Antrozous koopmani, the only one ever caught alive for decades. This is a species similar to the pallid bat Antrozous pallidus of the arid western U.S. The Cuban pallid was previously known from a handful of isolated skulls and two specimens preserved in spirits collected in the early decades of the XX century. The feat his yet to be repeated. Antrozous koopmani is today the rarest of Cuban bats, and is presumed nearly extinct (Mancina, 2012).

The list is followed by the greater funnel-eared bat Natalus primus, a critically endangered species known alive only from the single location of La Barca cave in Guanahacabibes, extreme western Cuba. There it was rediscovered by biologist Adrian Tejedor in 1991. Tejedor has written several interesting articles and a monograph on the rare and interesting funnel-eared bats (Natalids) of Cuba and the Caribbean (Tejedor, 2011 and citations therein). Cuba has other two funnel-eared bats. One of them, Nyctiellus lepidus, is one of the smallest bats in the world, known in Cuba as the "butterfly bat". The other, Chilonatalus macer, is similar to the Natalus major on the right of the image below but smaller.  Cuban natalids are all are endemic.

Left: Pteronotus quadridens from Hispaniola. Right: Hispaniolan funnel-eared bat
Natalus major from Cueva de Los Patos, also in Hispaniola.
These are small insectivores that live only in caves.


Other interesting records include Myotis sodalis, likely an errant from Florida found mummified by G. Silva in the city of Havana during the winter of 1966 (Silva, 1983). Eumops perotis, likely a vagrant or erroneous record dating back to 1839, a tree-dwelling Lasiurus insularis found by Ricardo Viera on the banks of the Yumuri River, Matanzas, in 2004, and our rediscovery of Desmodus rotundus in 2003; the fifth vampire bat fossil record from Cuba, among other informative, but isolated discoveries (Silva, 1983; Viera, 2004; Orihuela, 2010; Orihuela et al, in prep.). To this adds an array of new species and new deposits rich in bat fossils (Silva, 1974; Suarez, 2005; Suarez and Diaz-Franco, 2003; Mancina and Garcia, 2005; Jimenez et al., 2005; Balseriro, 2011; Orihuela, 2012).

Most of these latter species, however, are either accidental records, critically endangered, extirpated or extinct today. In addition to the extant 26 species, there are 8 disappeared species for a total of 34 known to have existed in Cuba at least during the last 20,000 years. The complex account of Cuban bat extinctions is reserved for an upcoming post; a topic most interesting to me, and the focus of most of my research.

Stay tuned!


The greater Cuban funnel-eared bat Natalus primus, severely endangered
and extant only in Cueva la Barca, Guanacahabibes, western Cuba.
Digital painting by, and copyright of Adrian Tejedor.


References

There are more citations, especially on area restriction, bat habitat, feeding, and climatic changes of the Quaternary that, if included, would have made this post a bit more tedious. I think, however, that the references below, in addition to the work of Angel Soto-Centeno, David Steadman, Danny Rojas and Liliana Davalos, will provide a good background for those interested in keeping up with this ever-growing body of literature.

Balseriro, F. 2011. Los murcielagos extinctos. pp: 171-177 en Borroto-Paez, R. y C. A. Mancina (eds) Mamiferos en Cuba. UPC print, Vaasa

Jiménez, O., M. M. Condis, and E. García. 2005. Vertebrados post-glaciales en un residuario fósil de Tyto alba scopoli (Aves: Tytonidae) en el occidente de Cuba. Revista Mexicana de Mastozoología, 9:84-111.

Koopman, K.F. 1958. A fossil vampire bat from Cuba. Breviora 90:1-4.

Suárez, W. 2005. Taxonomic Status of the Cuban Vampire Bat (Chiroptera: Phyllostomidae: Desmodontinae: Desmodus). Caribbean Journal of Science 41 (4):761-767.

Gonzalez, Alonso, et al. 2012. Libro Rojo de los Vertebrados de Cuba. Editorial Academia, La Habana. See "Mamiferos" pp:269-291 by mastozoologist Carlos Mancina.

Mancina, C. A., and L. Garcia. 2005. New genus and specis of fossil bat (Chiroptera:Phyllostomidae) from Cuba. Caribbean Journal of Science, 41: 22-27.

Mancina, C. A. 2011. Introduccion a los murcielagos pp: 123-133 en Borroto-Paez, R. y C. A. Mancina (eds) Mamiferos en Cuba. UPC print, Vaasa

Orihuela, J. 2011. Skull variation of the vampire bat Desmodus rotundus (Chiroptera: Phyllostomidae): Taxonomic implications for the Cuban fossil vampire bat Desmodus puntajudensisChiroptera Neotropical 17(1): 963-976.

Orihuela, J. 2012. Late Holocene fauna from a cave deposit in Western Cuba: post-Columbian occurrence of the vampire bat Desmodus rotundus (Phyllostomidae: Desmodontinae). Caribbean Journal of Science, 46 (2): 297-313.

Orihuela, J., and A. Tejedor. 2012. Peter's ghost-faced bat Mormoops megalophylla (Chiroptera: Mormoopidae) from a pre-Columbian archaeological deposit in Cuba. Acta Chiropterologica 14(1): 63-72.

Orihuela, J., R. Viera, and L. Vinola. 2017. New bat records based on modern and fossil remains from the province of Matanzas, Cuba.  

Silva Taboada, G. 1974. Fossil Chiroptera from cave deposits in Central Cuba, with a description of two new species, and the first record of Mormoops megalophylla. Acta Zoologica Cracoviensia, 19: 33-83.

Silva Taboada, G. 1983. Los Murcielagos de Cuba. Editorial Academia, La Habana.

Suarez, W. and S. Diaz-Franco. 2003. A new fossil bat (Chiroptera:Phyllostomidae) from a Quaternary cave deposit in Cuba. Caribbean Journal of Science, 39:371-377.

Tejedor, A. 2011. Systematics of the funnel-eared bats (Chiroptera: Natalidae). Bull. Amer. Mus. Nat. Hist. 353.



Saturday, April 9, 2016

First Anniverary of Fossil Matter!

Fossil Matter turns one! How time flies. It has been a great year of rambling on old and new ideas. I am looking forward to another great year of research, discovery, and science.

And a great way to celebrate the ever ongoing process of science and the anniversary of my blog is by announcing the recent publication of my article Clay tobacco pipes from a colonial refuse deposit in fort San Severino, Matanzas Province, Cuba , in the International Journal of Historical Archaeology (available at Springer). It took nearly a decade to complete our research, and then finally find the time to write it, edit it, re-edit it, edit it once more, and did I say edit it again? Yes!



I co-wrote it/researched it with my colleague Ricardo Viera, who had the great opportunity to conduct the actual excavation at Fort San Severino (a subject of one of my previous posts), and to study the artifacts extracted there. He is also my co-author on our blog dedicated to the history of San Carlos de Matanzas, our city of birth in Cuba, where we took our first steps into the world of science and exploration.

In a gist, the article deals with clay tobacco pipes excavated from fort San Severino colonial-era latrines. These interesting objects provide a great insight into many aspects of the everyday life at the fort, for both the military personnel and the prisoners kept there.

Clay pipes were used to smoke tobacco at the fort. Because they are personal objects, used for personal entertainment or habit, in times of leisure, they can tell us a bit about their behavior and preferences. Also, they can hint about the socio-economics of the fort, and because the fort played such a central role in the city of Matanzas, it too can hint about socioeconomics there. For instance, the dominance of one type of pipe over another can suggest where these pipes were likely coming from, and thus hint with who the fortians were buying or trading. Or if the articles were recirculated or reused in hard times.


These personal objects had a very short life, meaning they broke easily and were discarded rapidly. This provides great insight into the age of the artifacts, and how long it took the deposit to form. If it formed out a whim of re-construction or day to day trash disposal.

The trash in the latrines of our deposit, date to a period after the mid 18th century, that is the 1770s, and through the 19th century (the 1800s) until the latrines were filled as the fort turned into a military prison toward the last half of the 19th century. The presence of pipes manufactured in Catalonia, in Spain, corroborate well with the large immigration of Catalan merchants in Matanzas during this period. During the late 18th century Matanzas was a mere outpost with incipient trade, low population, and riddled by hardship. It is not until the mid 19th century that Matanzas blooms into the second most important port in Cuba, a status that dubbed the city as the Athens of Cuba. The tobacco pipes, along with the other artifacts, thus provide a snapshot of life at the fort during this important socioeconomic shift. They speak volumes on life then.



The history of the fort and its archaeology are very interesting, but I will leave them for another opportunity. However, bits and pieces of that history gleam in the posts of our joint venue with Proyecto Progressus, and the articles of the few archaeologists that have actually worked the site (citations therein).

Unfortunately, our paper did not make it in time for this year's SAA (Society for American Archaeologist) held, as I type, in Orlando, Florida. But I would like to take this opportunity, instead thank all those researchers, friends, and colleagues that helped us along the way. They are Leonel P. Orozco, Adrian Tejedor, Roger Arrazcaeta, Odlanyer Hernandez, Peter Davey, Byron Sudbury, Osvaldo Jimenez, and other pipe archaeologists around the world.

Thank you. 

I look forward to yet another year of posts and more research, with the hope that it will contribute, at least a grain, in fostering an interest for our culture's historical sciences. The ancient philosophers said that learning and remembering history helps in advancing positively our society by not repeating the mistakes of the past and enriching our present. 


Monday, March 14, 2016

A Very Brief History of Zero


This post is in honor of Pi Day and Albert Einstein's birthday, both which we celebrate today. Although Pi is known to more than a million digits past the famous 3.14159, my post will be about zero, likely our most important number. 

The number zero is included in the sets of whole and complex numbers but not in the
set of natural numbers. Zero is a number placed in the neutral space between the positive and negative numbers on the number line, extending to negative and positive infinite, and thus is neither positive nor negative. Zero has no value and is considered null digit. Mathematicians consider zero an even number based on the premises that if even numbers, when divided by 2 leave no remainder, as odd number do, then is clear that zero is even (1). Moreover, others have stated that it is because if an integer “N” is called even if there exists an integer “M” such that N= 2M. From this, they infer that zeros evenness is clear because zero= 2 multiplied by 0. See (1) and (2) below.

The concept of zero was recognized before the existence of the negative integers was ever considered. Babylonian and Indian mathematicians first thought of the zero around the second to the fourth millennium before the birth of Christ (4000-2000 b. C). However, its real development occurred around 36 b. C. in Mesoamerica. Archeologists hypothesize that other Mesoamerican civilizations like the Olmec may have had some knowledge of the zero much before the Mayans because of number-like hieroglyphs found in their stone calendars, and the values they are supposed to represent. Mayans used mathematics for astronomy and counting. They used their calculations to measure time and to track the stars (2). The use of zero was important because the numeric system depended on the position of the symbol for value; each symbol or glyph represented a level. Zero represented the beginning or no value from where all values originated. The values had additive properties. Precise knowledge of the previous value was crucial to get to the next (4). 


The number zero does not equal emptiness or nothingness. It is the midpoint of our number line and is commonly used to indicate magnitudes or sizes. Think of how we use zeroes every day, in our money, measurements, etc. In fact, the text you are reading now is based on a binary code of ones and zeroes. Mathematics surround us with the number zero playing a central role. 

Cited bibliography


(1)Penner, Robert C. (1999). Discrete Mathematics: Proof Techniques and Mathematical Structures. World Scientific: pg. 34.

(2) “Numeración Maya” retrieved on 2/13/09 from http://es.wikipedia.org/wiki/numeraci%C3%B3n Maya.

(3) Barrow, John D. (2001). The Book of Nothing. Vintage.

(4) Dichl, Richard A. (2004). The Olmecs: America’s First Civilization. Thames & Hudson.

Wednesday, March 2, 2016

Why Do I Blog?


Most of us blog to communicate ideas, discoveries, news, and the excitement that accompanies discovery. I started this blog with the intention to promote and divulge interesting ideas and information about the sciences that study the past, and the understanding I have gathered through my own experience in learning and research. This, of course, is with the hope of reaching a curious and interested audience.


This ideal is important for several reasons. One is that most of the scientific data we gather through field and cabinet work is later published in specialized journals, but these journals and their content are not really accessible to the general population. Moreover, people do not have the time to keep up with the amount of articles and journals published at all times, or because they are difficult to read.

These create a breach between the most recent scientific discoveries that is of value or interest to us all. Unfortunately, this breach is also a source of mistrust and unhealthy-biased skepticism for science in general, largely due to misunderstanding or ignorance. In fact, this goes against the grain of science communication and education, and it creates a deep gap between mainstream scientific advance and public knowledge.

I have hoped to contribute, although I recognize on a smaller scale, by posting about the things that I am curious about in science, promoting the scientific rationale behind them, and my personal experiences in my journey of learning and researching within these fields. I try to explain processes to find the practicability, or even really the excuse for what we do.

But what is the excuse. What if that curiosity pays off in the long run? It does. Curiosity does pay off in the long run. Look around you. The world that surrounds us is a world created by curiosity, science and technology. Think of the computer or cell phone in which you read these lines. The principles that make these appliances are hundreds of years old, invented or idealized by curious people who had no idea that their curiosities will turn out to be practical or useful to societies of the future.

As a geoscientist, I am trained to use the present as the key to the past. We are constantly trying to recreate and reconstruct the past. But, we try to reconstruct the past in the hope that that knowledge will give us a better present and future. We use models and predictions to hypothesize and reconstruct both the past and the future. So can we reconcile what we do with the practicability of our curiosity in the scheme of time? I think so. Discovering something new or interesting is one of my greatest pleasures. If the present is indeed the only reality and a product construction of our minds, then what better way to spend one's lifetime trying to understand the world that surrounds us, the things that draw our curiosity, even if at the time they seem impracticable or useless. Most of all, sharing and distributing that knowledge makes the quest most rewarding. I think that time has shown that in science no discovery is useless. We must surely always try to answer the whys, and how, where and who of our curiosity, and science allows for that freedom of thought and exploration that can surely fill more than a lifetime, and no doubt continue to better society and enrich human life.


Sunday, February 21, 2016

Project Progressus: Archaeology of Conflict


As you can tell from my posts, I love history, either in the rocks, fossils, or human records. I have recently joined Project Progressus an international research group interested in the archaeology of belic conflicts and the material and collective memories that these events have left behind in Cuba and Latin America.

Project Progressus has a self-titled blog page of which Odlanyer Hernández de Lara, a Cuban archaeologist with extensive work experience in Cuba and Argentina, is the editor and main contributor of blog Progressus. Odlanyer is also the editor in chief of Cuba Arqueológica, a journal that specializes in Caribbean archaeology, but particularly in the communication of advances in archaeological research in Cuba.

The explosion of the USS Maine in the bay of Havana on February 15, 1898, as depicted by an unknown artist for the Muller Luchsinger & Co New York. This incident launched the Spanish-American War or the "splendid little war" as was dubbed by Secretary of State John Hay. 

The scope of the project is to promote and communicate advances concerning the recovery of the material remains and collective memories of battle-conflict archaeology in Cuba and Latin America. This includes not only elucidating aspects of relatively modern conflicts such as the Spanish-American war and the Cuban Missile Crisis but also of conflicts earlier in the colonial period. My colleagues and I will be contributing by participating in field work, workshops, organization, and writing additional posts to increase accessibility to the archaeological information that the project will generate.

I am excited to enter Progressus not only because I will be contributing to the body of historical knowledge and deepen my own about colonial Cuba, but also because I will get the opportunity to collaborate and learn from great archaeologists with a deep understanding of this subject.

Without much ado, the reader is thus redirected to Progressus page for further information and interesting future posts.



Thursday, February 11, 2016

Fossil Leaves of the Yumuri River Gorge in northern Cuba


Fossilized plants are among the rarest types of fossils. This is because there are many factors that prevent or allow for their preservation. One of these factors is the delicate nature and chemical composition of the plant leaves themselves. Leaves are delicate, thin, and devoid, except in rare instances, of hard or mineralized parts, and thus become fossils under very special conditions; often in exceptional conditions.

Plant remains become fossils usually as carbon or oxide films within clay or mud sediments. The chances of preservation increase if coupled with rapid burial in quiet, low energy water environments where they can absorb water, sink and settle to the bottom where they become covered with sediment and preserved. If in addition, the sediment is low in oxygen, there is less decomposition and increasing preservation. In this way, fossil leaves provide an array of indicators to the surrounding environment and their origin, and thus open a wide window to the past.

Fig. 1: Fossilized leaf and seed on the river gravels at the Yumuri river site.

This is the case of the Yumuri River gorge, near Matanzas city, in northwestern Cuba. It represents an interesting example of both fossil leaf assemblage and good preservation (Fig. 1 and 2). These fossil leaves represent an interesting case in the study of Cuban, and even the Caribbean palaeoflora. The first fossil plants in Cuba were reported by the German Johannes Felix in 1882. Ever since, fossil plants have been sporadically reported from Jurassic to the Holocene fossils (Leon, 1929) (Iturralde and Rojas, catalog available here).

The fossil leaves of the Yumuri river gorge are found within the complex arrangement of sandstone conglomerates and fossil muds of El Abra member, a variation of the Canimar formation (Iturralde, 1969). These are a mixture of small and medium pebbles, with rare fish and crab fossils within the finer sediments. This formation is very localized, existing only along the river gorge. It apparently dates between the late Miocene and the middle Pliocene. If so, this fossil leaf deposit can provide a great insight into the poorly known flora and paleoclimate of the region during that the last 6 million years. In itself a great wealth of information into the Cuban past.

Fig. 2: Sands and gravels beds of the Abra member of the Canimar fm. on the banks
of the Yumuri river gorge.

Let us start with the fossil leaves.

The shape and area of the leaves, and the type of sediment in which they are preserved, can provide an array of approximations (proxies) into the past climate and formation history of this deposit. There is a correlation between environment and the shape of plant leaves (Wilf et al. 1998 and 2000. Also, see Lindner, 2007 and citations therein). Plants with large leaves and smooth edges are most common in tropical and subtropical climates. Inversely, leaves with lobed and serrated edges, as is the case of maples, are indicative of temperate, colder climates.  The larger the area of the leaf is positively correlated with local weather such as precipitation and temperature (op. cit.). The Abra leaves, with their smooth edges, and mostly smooth elongated leaves, suggest warm, mean annual temperatures (MATs), likely greater than or about 28 degrees Celsius. The leaf margin analysis (of LMA based on the mm^2 area of the leafs) suggests warm tropical climate with mid-range precipitation (see Wilf et al. 1998 for tables).

Fig. 3: Small leaf within its fine sand tomb. Note the raised bumps on the surface, and the smooth edges.

When leaves fall they are usually spread very close to their source (Lindner, 2007). In this way, they can represent a very true local floral assemblage. The task of identifying the leaf species from El Abra was first tackled by  E. W. Berry, who reported over a dozen of species (Berry, 1936). These were mostly new species; a study that now will need revision, and is a poor indicator of age. Berry had already reported on fossil plants from the Pleistocene deposits in another of Matanzas's famous site, the San Felipe Tar Pits, near Marti (Berry, 1934). These studies of palaeofloras was followed by the notes of Roca (1922), and later Leon (1929).

Overall, the Abra fossil leaves suggests a past tropical warm and humid coastal biome. This would agree with the higher temperatures of the Pliocene, especially those of the mid-Pliocene. But once more, the better chronology is wanting here.

Fig. 4: A very small leaf attests to the fine degree of preservation of oxidized leaf film.

Fig. 5: This curved leaf may be an indication, that at least some leafs were dry
when they sank to the bottom sediments of the river.

The Abra leaves show other interesting details which pertain to their physical state at the time of burial (taphonomy). Some of the leaves seem to have been preserved in a dry state. Meaning that at least some of the leaves that were preserved were dry and probably windblown by the time of deposition. This is the case of the leaf in Fig. 5, which compares with a dried example of a Mahogany Swietenia mahagoni Fig. 6 below. See how it is curved and curled?


Fig. 6: A modern example of a fallen, dry Mahogany tree leaf,
very similar to that of Fig. 5 above.

Because the sediments were so fine a mixture of mud and sands, leaf detail was preserved. Including in some examples, the original state of the leaves as they were being pressed and preserved into the thin films they are now.

The fossil plants occur only within the beds of fine sediments. These fine sediments indicate a low energy deposition environment, such as still or quiet waters, or single event deposition, such a flood that settled out quickly (Lindner, 2007). This is so because low energy waters usually do not move larger-coarser gravels, pebbles or boulders. Only larger energy events can. Especially if they are to be moved for longer distances along the flood plains of a shallow river bank. The mixture of sands and gravels of multiple sizes may support this. This is observable in the beds where the finer clasts overlie the heavier larger ones. This is called, in sedimentation stratigraphy, a graded bedding.


Fig. 7: Assemblage of fossil leaves encased in the sediment,
at various levels of deposition. Look at the bent leaf above.

These graded beds form a succession of finer beds, following larger thicker sandy beds, which indicate a cyclic variation in the formation of the deposit that can be indicative of migrating river beds, or flooding planes as stated above.These beds have marked limits in-between them, indicating abrupt changes in sedimentation regimes. Some have considered them to be variations in a river- sea level influence- regression and transgression or increasing/decreasing sea level (Iturralde, 1969). This makes sense being so close to the mouth of the bay, and if indeed this region had been a shallow, young delta in the past, much before it was lifted as it is now.


Fig. 8: Possible seed encased in fossil leafs.
Note the abrupt bed plane bellow the leafs. 



In conclusion, taking all these variations of evidence together we can reconstruct a wooded river margin, shallow, low energy, and prone to flooding, in a tropical/subtropical climate. The clastic material is most likely coming from erosion of higher inner valley lands, filtering through the incipient river gorge into the flood plains of the river deltas into the yet nonexistent bay of Matanzas.


Fig. 9: Eroded and exposed fossil leaf at El Abra, Yumuri River Gorge in Matanzas.

This is part of one of my ongoing projects and much more work needs to be done. For instance, one of the greatest problems is defining the actual age of the sediments since there are a lot mixture and reworking of younger and older material within the same beds. The other would be to revise the taxonomy of the plants involved, and other organisms found in the deposit.

If you are a plant taxonomist who can identify these fossil plants and would like to collaborate, contact me.

In the mean time stay tuned!



Cited Literature

For a catalog of Cuban plants see Estudios de Plantas Fosiles de Cuba, prepared by the National Museum in Cuba.

For other interesting fossil plant discoveries in the circum-Caribbean see Velez-Juarbe Caribbean Paleobiology blog.

Berry, E. W. 1934. Pleistocene plants from Cuba. Torrei Botanical Club 61(5): 237-240.

Berry, E. W. 1936. A Miocene flora from the Gorge of Yumuri river, Matanzas, Cuba. John Hopkins Studies in Geology 13: 1-135.

Iturralde-Vinent, M. see his literature regarding Matanzas on Biblioteca Digital Cubana de Geociencias.

Lindner Dustra, T. 2007. Paleobotany and Paleoclimatology, Part 2: Leaf Assemblages (Taphonomy, Paleoclimatology, and Paleogeography) pp. 179-202 in Part 3 of E. A. M. Koutsoukos Applied Stratigraphy, Topics in Geobiology, volume 23.

Leon, Hermano. 1929. La flora flosil de Cuba en la actualidad. La Salle: 1-6pp.

Roca, M. 1922. Nota aserca de un yacimiento de fosiles vegetales del Abra de Yumuri, Matanzas, Cuba. Memorias de la Sociedad Cubana de Historia Natural 4: 120-124.

Wilf, P. S. L. Wing, D. R. Greenwood, and C. L. Greenwood. 1998. Using fossil leaves as paleo-precipitation indicators: an Eocene example. Geology, 26: 203-206.

Wilf, P. and C. C. Labanderia. 1999. The response of plant-insect associations to Paleocene-Eocene warming. Science 284: 2153-2156.