While the taxon Thecodontia is obsolete, the term thecodont remains in use as an anatomical description of teeth in bony sockets; in addition to species formerly in this group (such as crocodiles and dinosaurs), mammals also possess thecodont dentition, which evolved independently.
What is thecodont dentition?
Thecodont dentition is a morphological arrangement in which the base of the tooth is completely enclosed in a deep socket of bone, as seen in crocodilians, dinosaurs and mammals, and opposed to Acrodont and Pleurodont dentition seen in Squamate reptiles. This morphology was once used as a basis for the now-defunct taxonomic group Thecodontia .
What are the different types of thecodonts?
I have recognized three distinct lineages of thecodonts based on the configuration of ankle structure: Proterosuchia, Pseudosuchia, and Ornithosuchia (for the latter see Chapter 2). In these groups the nature of articulation of two large ankle bones, the astragalus and calcaneum, is the basis for classification.
What are the characteristics of thecodonts?
Thecodonts are characterized by certain shared primitive features, such as the antorbital fenestra (an opening on each side of the skull between the eye sockets and the nostrils) and teeth in sockets.
Are coconuts mammals?
The notion that coconuts are the same as mammals is predicated on a concept known as morphology — or the notion that animals can be biologically grouped together based on the fact that they share the same structural qualities. And in morphological terms, there’s a decent surface-level argument that coconuts are mammals.
What animals are thecodont?
thecodontian, archaic term formerly applied to any member of a group of primitive archosaurs (“ruling reptiles”) thought to include the ancestral stock of all other archosaurs, including birds, dinosaurs, pterosaurs (extinct flying reptiles), and crocodiles. The name thecodont means “socket-toothed.”
Are all tooth bearing mammals thecodont?
Except mammals, thecodont type of teeth is found in crocodiles and in some fishes (Haddock, Garpike and Barracuda). Among vertebrates except thecodont, acrodont and pleurodont type of dentition is found.
Are reptiles thecodonts?
Thecodontia (thecodonts) 'Tooth-in-socket' reptiles, and the most primitive order of the Archosauria ('ruling reptiles'), ranging from the Upper Permian to the Upper Triassic. They were ancestral to the dinosaurs, pterosaurs, and crocodiles.
Are crocodiles thecodonts?
So, the correct answer is 'Thecodont'
What are types of mammalian teeth?
Mammal teeth can look really different from each other. But mammals' mouths have four main types of teeth: incisors, canines, premolars, and molars.
Do humans have Thecodont teeth?
Therefore, human teeth can be categorized as monophyodont, diphyodont, thecodont, heterodont, and bunodont. Hence, the correct answer is option C.
Do lizards have penises?
Two Is Better Than One. Snakes and lizards have not just one, but two penises, called hemipenes. University of Sydney researcher Christopher Friesen says having two hemipenes may benefit males during mating.
Are birds thecodonts?
Birds are placed in the Archosauromorpha, which includes the ancient thecodonts and their descendants–crocodiles, dinosaurs, pterosaurs, and birds. Of animals living today, ornithologists consider birds most closely related to crocodiles. The question isn't whether birds evolved from thecodonts, but WHEN.
Is thecodont still alive?
Thecodont ("socket-toothed" reptile), now considered an obsolete term, was formerly used to describe a diverse range of early archosaurs that first appeared in the Late Permian and flourished until the end of the Triassic Period.
When did Thecodonts go extinct?
They most likely went extinct from an asteroid during the Late Triassic Period some 200 million years ago, and that was probably the most important reason as to how the dinosaurs came to rule the Earth.
Are Thecodonts extinct?
any of various reptiles of the extinct order Thecodontia, occurring in the late Permian to late Triassic periods and characterized by teeth set in sockets.
What animals are acrodont?
Commonly kept species of lizards seen in practice with acrodont dentition include bearded dragons (Pogona vitticeps), Asian water dragons (Physignathus concinnus), Australian water dragons (Physignathus lesueurii), frilled dragons (Chlamydosaurus kingii) and all Old World chameleons.
Are all mammals heterodont?
The typical mammal has teeth adapted to different functions and morphologically divisible into incisors, canines, premolars, and molars (any or all of which can be lost evolutionarily). A few mammals (e.g., porpoises, armadillos) are homodont, with little or no differentiation among their teeth.
What is thecodont type teeth?
Thecodont dentition is a morphological arrangement in which the base of the tooth is completely enclosed in a deep socket of bone, as seen in crocodilians, dinosaurs and mammals, and opposed to Acrodont and Pleurodont dentition seen in Squamate reptiles.
What is thecodont diphyodont and heterodont?
Answer : C. Solution : Thecodont, diphyodont and heterodont teeth are char acteristic of mammals/man. Loading Books.
What animals are acrodont?
Commonly kept species of lizards seen in practice with acrodont dentition include bearded dragons (Pogona vitticeps), Asian water dragons (Physignathus concinnus), Australian water dragons (Physignathus lesueurii), frilled dragons (Chlamydosaurus kingii) and all Old World chameleons.
What class are mammals in?
Mammals are members of Class Mammalia and are distinguished by their presence of hair follicles, mammary glands, and the distinct design of their nose bones.
What are the traits of coconuts and mammals?
The other trait that coconuts and mammals both have in common is the fact that they grow hair or fur. In mammals, fur serves as a method to insulate their bodies against the cold, although many animals have designed specialized secondary purposes for the fur — as is the case with cats developing whiskers as sensory organs or the seasonally changing camouflaged of a snowshoe hare’s fur. Even mammals that initially wouldn’t seem to have fur — such as whales and naked mole rats — possess it in small quantities.
What is coconut milk?
A bottle with fresh coconut milk for skincare, with a fresh coconut . Coconut milk is processed using the meat inside of coconuts, whereas milk from mammals is produced from the mammary gland.
What is the outer layer of a coconut?
At first blush, the hairy exterior of coconuts would appear similar to the furry surface of mammals, but looks can be deceiving. Instead, the fibers of coconuts are the outer layers of the husk, and the husk serves as a hard carapace protecting the nut inside. That allows the coconut to fall from their tree and resist attacks from animals while the seed inside has a chance to germinate.
What order do coconut trees belong to?
Coconut trees belong to Order Arecales, which cover a narrow variety of flowering plants. Most varieties of flowering trees belong in this order. That means that coconuts themselves are both flowers and seeds.
What class is a coconut tree?
Bringing things back to where we began, the coconut tree falls into Class Arecaceae, which by modern definitions is the only existing class that falls under the purview of Order Arecales. That puts coconut trees in the company of palm trees — certainly a far cry from the apes, elephants, and mice that belong to Class Mammalia.
Which kingdom is the second highest in taxonomy?
The second highest classification in taxonomy is the kingdom. Mammals belong to Kingdom Animalia, which is comprised mostly of organisms that reproduce sexually and are usually mobile. Most members of this kingdom also ingest external sources for nutrients. The other five kingdoms account for plants, fungi, and three types of microscopic organisms.
What are the four suborders of Thecodontia?
Traditionally, the order Thecodontia Owen, 1859 was divided into four suborders, the Proterosuchia (early primitive forms, another paraphyletic assemblage), Phytosauria (large crocodile-like semi-aquatic animals), the Aetosauria (armoured herbivores), and the Pseudosuchia (see e.g., Alfred Sherwood Romer 's Vertebrate Paleontology and Edwin H. Colbert 's Evolution of the Vertebrates ). Of these, only phytosaurs and aetosaurs constitute monophyletic groups, and the term Pseudosuchia was simply a catch-all term for any species that didn't fit in one of the other three sub-orders. Pseudosuchia as used in recent literature is a stem-based taxon that includes crocodile -line archosaurs, or all archosaurs (including crocodilians) that are more closely related to crocodilians than birds .
What is the term for a group of reptiles that were found in the Permian period?
Thecodontia. Thecodontia (meaning 'socket-teeth'), now considered an obsolete taxonomic grouping, was formerly used to describe a diverse "order" of early archosaurian reptiles that first appeared in the latest Permian period and flourished until the end of the Triassic period.
What is the name of the category incertae sedis?
Robert Carroll, in his book Vertebrate Paleontology and Evolution (1988), replaces Pseudosuchia with Rauisuchia, Ornithosuchia, and the traditional category incertae sedis (of uncertain placement), while retaining the other three suborders.
Is thecodont an anatomical term?
While the taxon Thecodontia is obsolete, the term thecodont remains in use as an anatomical description of teeth in bony sockets; in addition to species formerly in this group (such as crocodiles and dinosaurs), mammals also possess thecodont dentition, which evolved independently.
Is thecodontia a paraphyletic taxon?
All more recent cladistic studies (e.g., Jacques Gauthier 1986) have confirmed that the traditional Thecodontia is indeed a paraphyletic taxon, the members of which are not united by any shared derived characteristics. As the association of the name with the outdated concept proved to be very strong, it is now considered a historical term only, and its current usage has been abandoned.
Is pseudosuchia a crocodile?
Pseudosuchia as used in recent literature is a stem-based taxon that includes crocodile -line archosaurs, or all archosaurs (including crocodilians) that are more closely related to crocodilians than birds .
What are thecodonts based on?
I have recognized three distinct lineages of thecodonts based on the configuration of ankle structure: Proterosuchia, Pseudosuchia, and Ornithosuchia (for the latter see Chapter 2). In these groups the nature of articulation of two large ankle bones, the astragalus and calcaneum, is the basis for classification. In Proterosuchia, these bones are firmly articulated without any movement between them. This is the most primitive lineage, and includes various early forms such as Archosaurus, Proterosuchus, and Erythrosuchus. Proterosuchians were powerful, big-headed predators, with sprawling limbs similar to the crocodilians.
Why did thecodonts' chances of survival deteriorate?
Their chance of survival deteriorated as the lowland plants became scarce in the more arid climates. With the emergence of the running prey population, thecodonts were unable to meet their food requirements. They could not escape direct interactions with the dinosaurs during the condition of extreme stress.
The Case For Coconuts as Mammals
The Case Against Coconuts as Mammals
- The case for coconuts to be considered as mammals is already tenuous, but underlining the dubious nature of using the terms milk and hair to define traits of coconuts only dances around the issue of why coconuts aren’t mammals. Because while finding morphological similarities can help us understand how different organisms are related to one another, the ultimate goal of taxonom…
Where Coconuts Fit in The Taxonomy
- But if coconuts don’t share a recent enough ancestor to be classified as mammals, how closely are they related? And how did they manage to develop similar traits despite having such distant ancestry? We can figure that out by working our way up through the taxonomy. 1. Mammals are members of Class Mammalia and are distinguished by their presence of hair follicles, mammary …
The Conclusion: Are Coconuts Mammals
- Officially and unequivocally, coconuts are not considered mammals. While they do share some interesting characteristics with mammals, coconuts are considered fruit – not mammals. Next Up: The 10 Largest Beetles in the World