Rodents gnaw bones

Rats eat dead bodies; be it human or another organism. These animals are mostly plant eaters, but mice and rats have evolved to ingest human waste, meat, fat, and including bones. This behavior is peculiar and important to us, those that study bones from the fossil or archaeological record.




Figure 1. Extensive gnawing by gray squirrels Sciurus carolinensis. Note the parallel, fan-shaped grooves.

Many organisms are instantly attracted to human waste and trash. Also to animal and human burials. It seems that rodents are attracted to the bones the most, which they gnaw and chew to acquire calcium salts and other nutrients. Gnawing also helps them file their ever-growing teeth.

This physical activity leaves physical evidence: characteristic, almost unmistakable, double grooved, fan-shaped marks on the objects they gnaw. For paleontologists, archaeologist, and forensic anthropologists, these marks are important and diagnostic of burial conditions, timing, and environment.




Figure 2. Gnaw-marks made by the Brown rat Rattus norvegicus. Note and compare to figure 1.
The grooves made by mice and rats are much straighter, and closely packed, with a smaller width.

Research during the past decades has shown that these marks are tell-tell signs of exposure and scavenger activity. A cadaver that is exposed, or unburied, attracts dogs, raccoons, and rodents, which eat, chew, and gnaw the parts that are exposed, available, or that are most attractive to them, leaving their markings behind. Several of them, like the African porcupine, take bones back to their burrow, where over the years, a collection or cache of bones builds up. These animals are modifiers, and their modifications can help determine how long those remains were unburied and who had access to scatter them.

In the case of rats, it had been assumed that they were most attracted to old, dry bones. But evidence from human and animal cadavers had been contradictory. A recent article, “Rodents as Taphonomic Agents” by Walter E. Klippel and Jennifer A. Syntelien, discuss this very issue. They found that in fact, rats are most attracted to fresh bones, especially those that still preserve yellow marrow, and fat. Remains with these characteristics are usually less than 30 months old, even under direct exposure to the elements and other modifiers. Their experiment showed that rats and canids (dog family), preferred fresh remains; usually, those that were less than a year old.

On the other hand, experiments on body farms, show that other rodents like squirrels do prefer older, dry bones, that have been exposed over several years. This is important because it can provide a confirmable timetable to estimate time of deposition and exposure for remains that bear these markings. For forensic anthropologists, the identification of these marks (along with other indicators such as insects and vegetation) can provide a time-since death, in the case of human cadavers resulting from accidents or homicides. For paleontologists and archaeologists like me, they can provide evidence of a nearby scavenger fauna, or proximity of several scavengers to human dwellings, and the approximate time of burial or exposure for those remains. Overall, providing much more information that can be gleaned from the bones alone.



Figure 3. Rodent marks made by a Cuban hutia (likely the large Capromys sp.), on a extinct hutia's femur shaft.
Note that there are characteristic, smaller, perpendicular striations.

We have found similar markings in Cuban archaeological deposits, but these are not referable to rats or squirrels since these rodents are not native to the island. However, they are referable, based on size, to the Cuban native hutias; rodents of the family Capromyidae, with several endemic species on the island. These markings suggest that hutias also were attracted to indocuban refuse, where they could gnaw on bones. The variation in the size of the marks also suggests that more than one species gnawed on refuse bone-remains that Cuban Indians discarded. Our evidence indicates that capromyid rodents were the most important bone dispersers and modifiers on the archaeological and paleontological deposits of the island much before Columbus rediscovered the New World (see Orihuela, Jimenez and Garcell, 2016).



Figure 4. Rodent gnaw marks on the distal end of an extinct hutia's tibia.
These smaller marks were likely made by a medium sized hutia, spiny rat
from Cuba's extinct fauna.

But how quickly did they seek out the bones? Or for how long were the remains available for these rodents? What role did the introduction of domesticated dogs affect these natural processes? We do not have concrete answers for these questions yet, but we have research on the way that can help clarify some of these issues and their importance in the study of the past and for historical sciences.

Stay tuned to find out!





Here is a brief bibliography for those that would like to read these interesting articles:


Fisher, J. W. (1995). Bone surface modifications in zooarchaeology. Journal of Archaeological Methods and Theory 2(1): 7-68.


Haglund, W. D. (1992). Contributions of rodents to postmortem artifacts of bone and soft tissue. Journal of Forensic Sciences 37:1459-1465.


Haglund, W. D., D. T. Ready, y D. R. Swindler (1988). Tooth mark artifacts and survival of bones in animal scavenged human skeletons. Journal of Forensic Sciences 33: 985-997.


Klippel, Walter E., y Jennifer A. Synstelien (2007). Rodents as taphonomic agents: Bone gnawing by brown rats and grey squirrels. Journal of Forensic Sciences, 52(4):765-773.

Orihuela, J., O. Jimenez Vazquez, and Jorge F. Garcell (2016). Modificaciones tafonomicas bioticas en restos oseos de depositos arqueologicos y paleontologicos en las provincias de Mayabeque y Matanzas, Cuba. Cuba Arqueologica.

 

Trilobites: Cockroaches of the Paleozoic Seas

Trilobites were the sea cockroaches of the paleoworld. They were marine arthropods, highly adapted to multiple types of ocean ecosystems and diets that included all sorts things from the ocean bottom. This versatility and diversity helped them dominated the oceans for over 320 million years. Yes! That’s millions of years! To put in context, dinosaurs ruled the world for nearly 200 million years, whereas us humans, as a recognizable biological species, have existed for only a mere 300 thousand years. That’s less than ten percent the time trilobites existed on the planet.

Asaphus, a trilobite genus common in the Ordovician

Trilobites belong to the animal phylum Arthropoda. Arthropod means jointed legs, one of the characteristics that define the group of segmented, jointed-leggedness, hard-bodied animals that include the insects, spiders, scorpions, crabs, and lobsters. 

 

Horseshoe crab Limulus polyphemus from the Gulf of Mexico.
Note the segmented body, carapace, and jointed legs.
These are characteristics of the Arthropods.

 

Trilobites appeared on the Earth’s fossil record since the early Cambrian, around 540 million years ago, and went extinct during the massive extinction event that took place in the Permian-Triassic, around 250 million years ago. Trilobites had suffered previous minor extinctions before. The first occurring soon after their origination, during the late Cambrian, around 485 million years ago. 

 

Yet, their acme or time of greatest diversity and distribution, occurred during the Ordovician, and lasted for millions of years until the Devonian period, when fish-like predators began to keep them in check. Their large eyes, capable of all-around vision, and hard segmented bodies (carapace) likely arose out of the necessity to look out and scape from such predators. Their interesting and unique eye characteristics were reminiscent of frogs. For that reason, scientists gave them names such as Phacobs rana, or “frog-like eyes”, best known from fossils commonly found in northeastern North America. 

 

Phacops rana: trilobite species common during the north American Silurian-Devonian.
Note its segmented, frog-like eyes with minute lenses.

Trilobites inhabited shallow, shelf, marine environments. By having eyes and eyespots on the top of their heads, trilobites could watch the world above their backs. The hard, segmented body, allowed for multiple forms of locomotion, swimming, and flexibility. Some species were more swimmers, others more bottom crawlers. Their tracks are known from rocks made from ocean bottom muds. They fed mostly on anything, from small organisms to organic matter and sea bottom detritus. This included dead organisms that fell down to the ocean floor. This made them, sort of, ocean bottom vultures or cockroaches. That goes besides their obvious physical similarity.

An analogous species today would be the horseshoe crab or lobsters.

 

Horseshoe crab Limulus polyphemus from the Gulf of Mexico.

 

Few research abstracts: 2015 - 2017

As the first blog post of the new year, this fulfills one of the goals of this page: to put new research discoveries, curiosities and research findings in the view of the general public. I will be sharing a few of my most recent research findings through the abstracts of their journal publications.

Thus, without much ado, here they are:



Spanish (Catalonian) clay tobacco pipes from Castillo de San Severino; early-mid XIX century

The clay tobacco pipes of Castillo de San Severino fort (Matanzas, Cuba): typology, spectroscopy (SEM-EDS) and contextual analyses

Here we provided a detailed study of a clay tobacco pipe collection, based on typology and using energy dispersion spectroscopy (SEM-EDS), recovered from fort Castillo de San Severino, Matanzas, Cuba. The pipes came from a trash deposit that dates to between the late XVIII century and the late XIX century. The collection includes pipes of north European traditional typology, such as Dutch and English, plus reed-stemmed pipes, including pipes from Catalonia (Spain) and eastern Mediterranean
such as the Balkans. The EDS analysis suggested that the samples studied are not likely of local manufacture, or manufactured with local clays. Our study, based on historic documents and artifact analysis, contributes to the general history of the fort by providing an interpretation of the socioeconomic factors controlling the culture of pipe smocking at the fort. Our data adds valuable information on the archaeology of these portable artifacts in the fort and the region.


New Stereoviews of San Jose de la Vigia, Matanzas, Cuba: A historical contribution and new archaeological perspectives

Here we reported five stereoviews that reveal details of Matanzas city during the mid-XIX, particularly of the Plaza de la Vigía and the fort of San José de la Vigía, previously unexplored in the local historiography. These rare photographs are an invaluable resource to the historic, preservation and archaeological research of these features, which such as the fort, are today long gone. In comparison to the known etchings and sketches, these photographs constitute a less distorted record of the city.

Cover of Cuba Arqueologica, prestigious journal of Caribbean archaeology, with a
stereoview photograph of Plaza and fort La Vigia, Matanzas, Cuba, in 1859.

First report of the marine mollusk Busycon perversum (Gastropoda: Busyconidae) from the archaeological site of El Morrillo, Matanzas, Cuba

Here we reported the presence of the mollusk Busycon perversum in the archaeological site of El Morrillo. Although several species of Busycon are known from colonial sites in Havana, this constitutes the first confirmed record of this alocthonous species in region of Matanzas. This finding, as in the cases in Havana, are interpreted as importation or exchange between Floridian Amerindians, such as the Calusa or Tekestas, in Cuba during the early centuries of the island's colonization. However, it could have been introduced in Cuba also by sailors visiting the Gulf of Mexico and Florida.

Busycon perversum juv. from El Morrillo

The First Battle of the Spanish-Cuban-American War (1898): Insights from a Historical and Archaeological Perspective

The Spanish-Cuban-American War of 1898 constituted not only the events leading to the start of the first modern war but also marked the beginning of the colonialist expansion of the United States throughout the world. The explosion of the USS Maine in Havana’s harbor has often been interpreted as the excuse used by the US to get involved in the Cuban War of Independence; a war that Cubans and Spaniards had been fighting since 1895, but rooted since 1868. Previous research has traditionally focused in the naval encounters of the Spanish and US fleets in Santiago de Cuba, or the end of the war with the occupation of Puerto Rico, the Philippines, and Guam, thus underestimating the role of the Cuban troops and leaving the early events of the war poorly explored. Our research focuses on the first battle of the war, which occurred on Matanzas Bay, Cuba, on April 27th, 1898. Historic documentation from Cuban, Spanish, and US archives is analyzed, and compared to the available archaeological data, to deepen the understanding of the defensive and offensive strategies employed, and their impact on the media and their publicist strategies.

Image, mounted on glass of the bombardment of Matanzas by three USS warships in 1898

Contribution to the chronology and paleodiet of an aboriginal individual excavated in the archaeological site of El Morrillo, Matanzas, Cuba

El Morrillo, an archaeological site localized on the margin of the Canímar River, in the bay of Matanzas, is considered one of the most important agroceramist culture deposits of western Cuba. Despite its importance and richness, only one radiocarbon date, based on charcoal, had been reported from this site since 1966. Here we provide the first AMS 14 C date measured directly from human remains, excavated in 2009, along with a carbon and nitrogen stable isotope analysis to infer the diet of this individual. The AMS 14 C provided a radiocarbon age of 420±40 rcyBP (AP) (2σ calAD1420-1523). These results indicate a post-Columbian time of burial, likely near or during the first decades of the Cuban conquest early in the XVI century. The stable isotopes suggest that the individual had a mixed diet, with intermediate carbon consumption, and high on marine/riverine resources, which suggest the exploitation of the nearby coastal and fluvial ecosystems. These values are generally comparable to several populations of similar filiation in the Greater Antilles. Our results highlight the importance of El Morrillo in the study of agroceramist communities in Cuba and the Caribbean.

Cover of Cuba Arqueologica with an architectural plan of La Laja,
interesting water locked fortification planed for the center of the bay of Matanzas
that was never completed.

Plans for a fort in the middle of the bay of Matanzas: La Laja

The construction of fortifications in strategic or advantageous localities constituted a main method of military landscape colonization. With the economic boom of Matanzas's city, in northwestern Cuba, the importance of the growing port incited the planning of several strategic defense points, but many of them were not completed. One of them, named La Laja, planned in the center of the bay was one of such strategic localities selected for a fortification and lighthouse. Here we analyzed and reported eight unpublished plans that document several of the different projects planned for La Laja. These plans provide insight into the constructive dynamics and the evolution of defense fortifications surrounding the port and city, in this case where the bureaucracy and demolition of fort La Vigia prevented the completion of what could have been a singular and unique engineering feature.

To our great joy, several of our paper's illustrations made the journals front image. None of these accomplishment would have been possible without the help and encouragement of my coauthors, Ricardo Viera Munoz, Odlanyer Hernandez de Lara, Leonel Perez Orozco, and Osvaldo Jimenez. Moreover the patronage and encouragement of Adrian Tejedor, Herman Benitez, and many others that with their guidance and help, made our research process fun and educational. Our most sincere thanks.

For more information visit our other blogs and pages:

San Carlos de Matanzas

Progressus: Arqueologia, Patrimonio y Desarrollo Social

Research Gate

Visit us and stay tuned!

Nesophontes: The Discovery of the first Greater Antillean Island Slayer

Nesophontes are a small group of shrew-like mammals with a very primitive past that reaches as far back as the Cretaceous - when the dinosaurs roamed this planet. We owe its discovery to Harold H. Anthony, one of the most proliferous pioneers of Caribbean vertebrate paleontology.

Original illustration of the type description of Nesophontes edithae H. E. Anthony 1916

The genus Nesophontes is today grouped within the Eulipotyphla order. This is a group of basal placental mammals that are today considered ancestrally associated to Solenodon and other North American extinct shrew-like micromammals, but surprisingly, not to the African tenrecs.  They were small, likely venomous, nocturnal and semi-fossorial mammals endemic to the Great Antilles, where they had a widespread distribution, with the interesting exception of The Bahamas and Jamaica.


Solenodon paradoxus from Hispaniola at the Mammalogy collection of the AMNH

By 1915, H. E. Anthony had a hint of the existence of Nesophontes from fossils found in the island of Puerto Rico. Dr. Franz Boas, the German-American father of modern anthropology, had sent material from his expedition in Puerto Rico to the American Museum of Natural History in New York City (AMNH) that same year. Anthony worked as a paleontologist there, and from Boas's material he extracted the first incomplete specimens of Nesophontes. But these were not enough to describe a new species.

Left: Franz Boas, German American Anthropologist, circa 1916. Right: Harold H. Anthony, circa 1930s.

In fact, it was Dr. Anthony's wife, Edith I. Anthony, who on July 19, 1916, discovered the first undoubtable evidence of the existence of this peculiar mammal in Cueva Clara, near Morovis, Puerto Rico. Anthony, in honor of its wife, named the type species Nesophontes edithae.

Type specimen of Nesophontes edithae AMNH 14174, collected by Mrs. Anthony in 1916

The study of Nesophontes is forever tied to the efforts of Anthony, the discovery of his wife and the material sent by Franz Boas. Gerritt S. Miller and Glover M. Allen, in addition, played a role too in the further discovery and study of these peculiar extinct mammals. In 1919, Anthony described a new species, Nesophontes longirostris, this time from a cave deposit in Daiquiri, southeastern Cuba.

H. E. Anthony would continue to work for the AMNH until the 1960's as one of the museum's most respected mammalogists, paleontologists, and curators.

Please stay tuned for an upcoming post on Solendon!

Our New Book: Matanzas in the Viewfinder of Time!

With great pleasure and excitement, after prolonged anticipation, here I present our latest publication, our book “Matanzas en el Visor del Tiempo” or Matanzas in the Viewfinder of Time. It took several years of research to complete, from dream to reality, and it is now finally ready. We are proud that it will fill-in a gap in the history of our hometown, Matanzas city, Cuba. No doubt, the sacrifice and long wait it took to see it published was worthwhile. We hope it is as enjoyable to you as it is for us.

Concord Bridge, completed in 1878 by Spanish-born architect Pedro Celestino del Pandal y Sanchez

This book was written in Spanish by Leonel Pérez Orozco, Matanzas City Conservator, Luis R. González Arestuche, Matanzas-born architect and architecture historian, plus archaeologist Ricardo Viera Muñoz, and myself. Karell Bofill Bahamonde graced our work with his graphic design and modern photographic editing. And last but not least, the modern photographs of Jorge I. Rodríguez.



First leaf of Matanzas en el Visor del Tiempo (2017) Ed. Bolona.

Our book was idealized as a two-volume visual and historical compendium. We started it in 2012 and was completed by 2014, when it was tentatively published by the Felix Varela, publisher of the University of Havana. However, several reasons precluded it from being finally printed there. Finally, thanks to the help of the Office of the Conservator and city Historian of Matanzas, and Havana, specially Eusebio Leal Spengler, our book was published this month. It is a 725-page single volume with over 300 previously unedited and unpublished photographs, few as early as 1859 up to the present.



Matanzas's Cathedral of San Carlos de Borromeo,
patron saint of the city and one of its most emblematic locations.
View from early XX century and present.

This current edition (2017) outlines the architectural evolution and history of Matanzas city. Many of the photographs represent long-gone locations and buildings. It shows a full spectrum of lost patrimony, in the way of architecture and landscape design, that has characterized the changes of the last 100 years. It shows Cuban life as it was.

Some of the oldest photographs were taken by American photo-entrepreneurs, established in New York City, who sent their photographers to capture the “exotic” world of Spanish Cuba. Among them was E. Anthony and Co., who sent their photographer George N. Barnard to Cuba for their album “Cuban Views” (1860) and “American Views” (1870).


One of the oldest photographs known of Matanzas city. This one was taken in 1859 by G. N. Barnard
for E. Anthony and Co. "Cuban Views" stereoview album.

We take this opportunity to thank those friends and colleagues whose collaboration, patience, and insight made, no doubt, a large impression on the pages of our book and our experience.

Thank you so much.


Recommended citation: Pérez Orozco, L., L. R. Rodríguez Arestuche, J. Orihuela León, and R. A. Viera Muñoz (2017). Matanzas en el Visor del Tiempo. Editorial Boloña, La Habana.

See our upcoming publication for more details:

Orihuela, J. and R. A. Viera (2016). Fotografias historicas de la bateria de San Jose de la Vigia, Ciudad de Matanzas, Cuba. Revista Arqueologica Cuba Arqueologica, 9 (1): 1-9.