Hello blog readers, here I provide a link to our article "Clay Tobacco Pipes from a Colonial Refuse Deposit in Fort San Severino, Matanzas Province, Cuba" published on the International Journal of Historical Archaeology, which Spinger Nature has kindly allowed us to share.
This article deals with the identification of clay tobacco pipes used for smocking by prisoners and soldiers of the fort's garrison between the late XVIII and through the middle XIX century. This small collection of smocking pipes, as personal portable objects, speak volumes to the pastime activities available at the fort. More so, it provides a small window into the origin and circulation of pipes.
Visit the link below to read more!
https://rdcu.be/6hvK
Stay tuned!
Tuesday, September 11, 2018
Thursday, August 16, 2018
Updated list of Cuba’s extinct birds
Cuba had a former, richly diverse bird fauna, most of which is today extinct. In recent years, the known species have seen revisions, additions, and deletions that have changed the topography of the species' roster. For the benefit of all those interested, here I provide an actualized list of Cuba’s extinct birds reflecting those changes.
This has been the recent topic of an article I have now submitted to an ornithological journal with the hopes that it may aid my peers in understanding the diversity of long-gone Cuban birds. But most especially, my intent has been to divulge in a single compendium an actualized list that reflects those recent changes.
Update: this paper is now published and available at the journal Ornitologia Neotropical here.
Much work it is jet to be done, and with the interesting new deposits being explored and researched in the Greater Antillean island of Hispaniola and The Bahamas, it would not surprise me to see Cuban species, even some of those we today consider endemics, appear in those contexts.
With that said, here is the list:
Supercohort: Dinosauria
Class: Aves
Order: Pelecaniformes
Family: Ardeidae Leach, 1820
(Herons and egrets)
This has been the recent topic of an article I have now submitted to an ornithological journal with the hopes that it may aid my peers in understanding the diversity of long-gone Cuban birds. But most especially, my intent has been to divulge in a single compendium an actualized list that reflects those recent changes.
Update: this paper is now published and available at the journal Ornitologia Neotropical here.
Much work it is jet to be done, and with the interesting new deposits being explored and researched in the Greater Antillean island of Hispaniola and The Bahamas, it would not surprise me to see Cuban species, even some of those we today consider endemics, appear in those contexts.
With that said, here is the list:
Supercohort: Dinosauria
Class: Aves
Order: Pelecaniformes
Family: Ardeidae Leach, 1820
(Herons and egrets)
Tigrisoma mexicanum
Swaison 1834, reported by Olson &
Suarez (2008). This is a Tiger-heron.
Order: Ciconiiformes
Family: Ciconiidae J.
E. Gray, 1840
(Cranes)
(Cranes)
Ciconia lydekkeri (Ameghino
1891), is considered a senior synonym of C. maltha (L. Miller 1910:440)
by Agnolin (2009).
Ciconia sp. This species was mentioned by Suárez & Olson (2003a: 151) .
Mycteria wetmorei
Howard 1935: 253. (See Iturralde et al. 2000; Suárez & Olson 2003a).
Order: Incertae
Sedis or Accipitriformes
Family:
Teratornithidae L. Miller, 1909
(large, near flightless terrestrial raptor birds)
(large, near flightless terrestrial raptor birds)
Oscaravis olsoni (Arredondo & Arredondo 1999:16)
(=Teratornis olsoni) amended and
redescribed by Suárez & Olson (2009:106).
Order:
Accipitriformes or Cathartiformes
Family: Cathartidae
Lafresnaye, 1839
(vultures and condors)
(vultures and condors)
Gymnogyps
varonai (Arredondo
1971:310) (=Antillovultur varonai). Amended by Suárez (2000a).
Cathartes sp. 1 or Cathartidae indet. 2. See Suárez
(2001c:110).
Family: Accipitridae
Vieillot, 1816
(hawks and falcons)
(hawks and falcons)
Amplibuteo woodwardi
(L. Miller 1911:312), reported
in Suárez (2004).
Buteo lineatus (Gmelin 1788:268), reported in Suárez
& Olson (2003b).
Buteogallus borrasi (Arredondo 1970) =Aquila borrasi Arredondo (1970) amended by Suárez
& Olson 2007.
Black-Chested Buzzard Eagle Geranoaetus melanoleucus Swan,
1922:67. Reported by Alexander Wetmore (1928).
Gigantohierax suarezi Arredondo & Arredondo 1999: 10. Now
includes specimens previously identified as Aguila borrasi (=Buteogallus borrasi).
Caracara creightoni Brodkorb 1959:353, reported by Suárez
& Olson (2003c:306).
Milvago
carbo Suárez &
Olson (2003:302).
Milvago sp. from Suárez & Arrendondo (1997).
Falco femoralis
Temminck 1922:121. This Aplomado falcon was reported by Suárez & Olson (2003b).
| Aplomado Falcon (Falco femoralis) near the town of Tinke, at the foot of the majestic Ausangate Mountain, Peru. |
Falco
kurochkini Suárez &
Olson 2001a:35.
Order: Gruiformes
Family: Gruidae
Vigors, 1825
(storks)
(storks)
Grus cubensis (Fischer & Stephan 1971a:565).
Family: Rallidae
Rafinesque, 1815
Nesotrochis picapicensis
(Fischer & Stephan 1971b:595), revised and amended by Olson (1974). This is an endemic near-flightless Cuban rail. Puerto Rico had a similar species.
Order:
Charadriiformes
Family: Burhinidae
Mathews, 1912
Burhinus sp. reported by Oscar Arredondo (1984). This is another form of water bird called the Double-striped Thick-knee that lives in Central and South America.
Family: Scolopacidae
Rafinesque, 1815
Gallinago kakuki
by Steadman & Takano (2016: 348). Formerly Capella sp. (Suárez 2004a). This is a type of sandpiper or snipe.
Order: Psittaciformes
Family: Psittacidae Rafinesque, 1815
Ara tricolor Bechstein 1811:64 (= A. cubensis
of Wetherbee, 1985). The Cuban macaw: see my previous post on this species here.
Family: Tytonidae
Ridgway, 1914
Tyto noeli Arredondo 1972a: 416. This species new
included Tyto neddi of Steadman & Hilgartner (1999) from Barbuda. This is a large barn owl, like the other species listed below.
Tyto pollens Wetmore 1937:436. This taxon now
includes Tyto riveroi Arredondo
1972b: 131. The rarest of all Cuban tytonids, known from a single locality.
Tyto cravesae Suárez & Olson 2015: 544.
Tyto sp. A small species reported by Suárez &
Díaz-Franco (2003: 375).
Family: Strigidae Leach, 1820
Bubo osvaldoi Arredondo & Olson 1994:438.
Pulsatrix
arredondoi Brodkorb,
1969: 112.
Ornimegalonyx oteroi Arredondo 1958: 11.
Ornimegalonyx
acevedoi Arredondo,
1982: 95.
Ornimegalonyx
minor Arredondo, 1982: 46.
Ornimegalonyx
gigas Arredondo, 1982: 47.
It is likely that all Ornimegalonyx represent a
single species. Their size disparity could be due to sexual dimorphism,
chrono-temporal or/and individual variation (Alegre 2002).
Order:
Caprimulgiformes
Family: Caprimulgidae
Vigors, 1825
Siphonorhis
daiquiri Olson,
1985:528. This is the endemic pauraque or Cuban Poorwill, a species of nightjar.
Order: Passeriformes
Family:
Rhinocryptidae Wetmore, 1930
Scytalopus sp. reported by Olson and Kurochkin (1987).
This is a small passerine bird commonly known as "tapaculo".
Family: Icteridae
Dolichonyx kruegeri
Fischer & Stephan (1971: 597). This is
likely a misidentified specimen of Bobolink (D. oryzivorus),
an uncommon transient species in Cuba (Garrido & Kirkconnell 2000: 218).
Wednesday, April 25, 2018
Ara tricolor: Cuba's extinct endemic macaw
Up to 150 years ago Cuba possessed three parrots in its avifauna-one of them a large and beautifully colored macaw.
Parrots belong to the bird family Psittacidae, of which Cuba has two representative genera and species: the endangered Cuban conure Psittacara eups (=Aratinga), and the better widespread Cuban parrot Amazona leucocephala. Up to the mid-XIX, Cuba also had a large macaw, Ara tricolor. The last known pair was shot in 1864 at La Vega, in the Cienaga de Zapata-the largest wetland swamp of the Caribbean archipelago. The ornithologists Johannes Gundlach and C. B. Cory believed that this species survived up until the later XIX century. In Spanish, these large parrots are known as guacamayos, which is the Arawak indian name, or papagayos, the Castilian.
Scientist recognize that other large Ara macaws existed in other islands of the Caribbean, but the Cuban macaw is the only one known from complete specimens, preserved as stuffed, mounted, or skins, and several skeletal parts found in paleontological and archaeological deposits.
Colonists that came to the island after Columbus’s rediscovery of the New World, documented the massive killings of these birds by amerindians, but mostly by conquistadors, who used them for food, plumage, or kept them as pets. In one occasion, Father Bartolome de las Casas records a mass killing of macaws at the indian town of Casaharta in 1513 by the natives for the sake of the colonists:
Bibliography
De Las Casas, Bartolomé (1560/1875). Historia de las Indias. Vol. 1-4. Imprenta de Miguel Ginesta (Press), Madrid.
Gundlach, J. C. 1876. Contribución a la ornitología cubana. Imprenta La Antilla, La Habana, 364 pp.
Gundlach, J. C. 1893. Ornitología cubana. Imprenta La Moderna, La Habana, 357 pp.
Wetmore, A. (1928). Bones of birds from the Ciego Montero deposit of Cuba. American Museum Novitates 301: 1-5.
Wiley, James W. and G. M. Kirwan (2013). The extinct macaws of the West Indies, with special reference to Cuban macaw Ara tricolor. Bulletin of the British Ornithologists’ Club 132 (2):125-156.
![]() |
| Watercolor of the Cuban macaw Ara tricolor circa 1800 by Jacques Barraband, a French zoological illustrator. From the Cuban macaw Wikipedia. |
![]() |
| Oil on canvas: "A moorhen, a gull, and a Scarlet Macaw by a stream in a landscape" by Philip Reinagle circa early XIX century. |
Scientist recognize that other large Ara macaws existed in other islands of the Caribbean, but the Cuban macaw is the only one known from complete specimens, preserved as stuffed, mounted, or skins, and several skeletal parts found in paleontological and archaeological deposits.
![]() |
| Painting of Ara tricolor by Francois-Nicolas Martinet, in 1765. |
Colonists that came to the island after Columbus’s rediscovery of the New World, documented the massive killings of these birds by amerindians, but mostly by conquistadors, who used them for food, plumage, or kept them as pets. In one occasion, Father Bartolome de las Casas records a mass killing of macaws at the indian town of Casaharta in 1513 by the natives for the sake of the colonists:
“[my translation] …the many things marvelous and abundance of food from many sources, bread and game, and fish, but above all of macaws, which if I have not forgotten, during the 15 days that we were there, at least 10,000 macaws were eaten. These were of the most beautiful in the world, which was a real shame to see them killed. Even the little native kids would climb trees to catch them…”
Las Casas also recorded the presence of a “different” macaw, with a white, not red, forehead on the island of Hispaniola. He mentions that when Columbus reached the island of Cuba, “nice, green macaws” were gifted to him by the natives (Las Casas, 1875:296, vol. 1). The colonists accepted these gifts, and many macaws were sacrificed for their beautiful feathers, which were to be sent to Spain as exotic souvenirs.
![]() |
| Mounted specimen of the Cuban macaw from the RMNH. Naturalis Biodiversity Center. |
It seems, by these accounts, that the Caribbean amerindians were also fond of keeping parrot pets. Yet still, during these early years of the conquest, “there were so many flocks of parrots, that they covered the sun”. This was not to last past the colonial era.
The causes of its final extinction are closely tied to human pressure: overhunting at first, and later, deforestation for agricultural development, most intensified during the XVIII and early XIX. During this time, the king’s preserves of forests were maintained and untouched until then by Real decree and accessed only illegally or under special grant by the king. But with the massive onset of agriculture deforestation for tobacco and sugar cane plantations likely drove these large birds to the few remaining forests of the island, Cienaga de Zapata being one of them, and one of the most protected even now. It was at these locations that a few naturalists secured the last specimens, treasures of American and European museums. Sadly, the only surviving mounted skin of Ara tricolor in Cuba was recently stolen from the Institute of Ecology and Systematics (IES) in the outskirts of the city of Havana. This was a gorgeous well-preserved specimen collected by Johannes Gundlach, and one of the most treasured specimens of the old Academy of Sciences, which are now housed at the Institute.
![]() |
| Cuban macaw Ara tricolor from the National Museum of IES in Havana, Cuba. This specimen has been recently lost or stolen. Courtesy of A. Tejedor. |
These rare representatives of Cuban macaws belong in museums, were they are taken care by specialists, people who have studied their whole lives to preserve specimens such as these, and where they are kept under special conditions, and where they can be studied by those that are interested. They do not belong in some collector’s cabinet. It is only hoped that the final itinerary of this specimen is secured, and that the collector protects the beautiful mounted specimen with the dignity it deserves-for the rarity it represents, and as a reminder of the vulnerability of the Earth’s fauna before human destructiveness.
Bibliography
De Las Casas, Bartolomé (1560/1875). Historia de las Indias. Vol. 1-4. Imprenta de Miguel Ginesta (Press), Madrid.
Gundlach, J. C. 1876. Contribución a la ornitología cubana. Imprenta La Antilla, La Habana, 364 pp.
Gundlach, J. C. 1893. Ornitología cubana. Imprenta La Moderna, La Habana, 357 pp.
Wetmore, A. (1928). Bones of birds from the Ciego Montero deposit of Cuba. American Museum Novitates 301: 1-5.
Wiley, James W. and G. M. Kirwan (2013). The extinct macaws of the West Indies, with special reference to Cuban macaw Ara tricolor. Bulletin of the British Ornithologists’ Club 132 (2):125-156.
Thursday, March 15, 2018
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.
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.
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.
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).
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.
| 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.
Thursday, February 15, 2018
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.
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.
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.
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.
| 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. |
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