Pisces (with fins) and Tetrapoda (with bare limbs). Environmental Biology of Fishes, 61(2), 125133. On this Wikipedia the language links are at the top of the page across from the article title. https://doi.org/10.1002/jmor.10661. Cell and Tissue Research, 228(1), 139148. To see the full list of the species, click here. Rays are marketed for food in many countries around the world, primarily in Europe and Asia, with about 126,000 short tons (roughly 114,000,000 kilograms) being marketed for food. 3. Chondrichthyes - Rays, Sharks, Skates, Chimaeras In: Vonk, J., Shackelford, T.K. Vigh-Teichmann, I., Vigh, B., Silva, M. M., & Aros, B. - 139.59.14.115. Vertebrates comparative anatomy, function, evolution, 7th edn. In A. Oppel (Ed. https://doi.org/10.1113/jphysiol.1951.sp004638. Cell and Tissue Research, 303(3), 391401. Fishes also have somatic sensory nerves, which are nerves that are responsive to stimuli from muscles or the skin. In the next five years it grows about 60 mm (about 2.4 inches) more toward its maximum recorded width of 25 cm (10 inches) in males or 31 cm (12.25 inches) in females. Diverse species of fish are included in the class, such as sharks, rays, skates, and chimaeras. | 1 https://doi.org/10.1007/s11160-010-9162-x. Osteichthyes have specialized taste buds, located either in their mouth or along whisker-like barbels. Google Scholar. (Note: It is rated PG but there are some graphic scenes involving shark finning), Sharkwater (2006)[Vimeo] Running time 1 hour 30 minutes. In J. C. Carrier, J. A., & Demski, L. S. (2004). Chondrichthyes Sensory Systems | SpringerLink Brain Structure and Function, 220, 11271143. Feeding/Digestion They digest the blood taken from other fish (host) directly in the intestines. Chondrichthyes' sensory systems are part of the nervous system responsible for receiving external and internal stimuli and translating them into nerve impulses that are transmitted to the central nervous system where they are processed. These are the Ampullae of Lorenzini. In Seminars in Cell & Developmental Biology. The Central Nervous System of Hagfishes Mark Ronan & R. Glenn Northcutt Chapter 464 Accesses 4 Citations Summary A brain and spinal cord constitute the central nervous system of hagfishes, the extant sister group of lampreys and gnathostomes among the craniates. Compagno, L. J. Class Chondrichthyes - The Tree of Life The mesencephalon sits superior to the diencephalon and contains the superficial white zone, central zone, deep white zone, and periventricular gray zone. As the density of the cartilage is less as compared to the bones it provides more flexibility and hence they can bend easily as compared to the bony fishes. Gardiner, J. M., Hueter, R. E., Maruska, K. P., Sisneros, J. In Greek, elasmo means Plate and branchia means gill, hence we can tell that long and broad flattened gills are the characteristics of these fishes. 11051112). Vision in sharks and rays: Opsin diversity and colour vision. Only their teeth, and sometimes their vertebrae, have calcium in them! Chondrichthyes and Osteichthyes have the following general characteristics: Both have endoskeletons and exoskeletons. The pineal organ of Raja clavata: Opsin immunoreactivity and ultrastructure. Heterocercal caudal fin (not symmetrical vertebral column runs into caudal fin). The telencephalon in some fishes is enlarged, giving them an exceptional sense of smell. Chondrichthyan - Respiration, reproduction & growth | Britannica Sharks: Dogfish, Whale shark, Angel shark, Ground Shark, etc. There are placoid scales covering the skin. Veronica Slobodian . Behavior and physiology of mechanoreception: Separating signal and noise. A., & Demski, L. S. (2004). Journal of Physiology-Paris, 102(46), 256271. All fish embryologically develop two eyes, although some groups of fish are functionally blind, whereas others have keen eyesight for spotting prey and avoiding predators. Die Parietalorgane. Google Scholar. https://doi.org/10.1111/j.1095-8649.2011.03214.x. Phylogenetic systematics of extant chimaeroid fishes (Holocephali, Chimaeroidei). https://doi.org/10.1038/421495a. 349402). There is no parental care after birth; however, some chondrichthyans do guard their eggs. Kajiura, S. M. (2001). Didier, D. A. (2021). Part of Springer Nature. (2009). Think of a fish, any fish at all (well, with the exception of a shark, a skate, or a ray). Denticles usually provide protection, and in most cases, streamlining. The pineal organ of Raja clavata: Opsin immunoreactivity and ultrastructure. Bony fishes have heavily ossified skeletons with true bone and include species such as carp, eels, and lionfish. These scales make their skin so rough it can be used as sand paper! The lateral line has nerves that are able to pick up sensory information about water displacement. ), Lehrbuch der vergleichenden mikroskopischen Anatomie der Wirbeltiere (pp. Olfactory morphology and physiology of elasmobranchs. Lisney, T. J., & Collin, S. P. (2007). Sensory biology of elasmobranchs. https://doi.org/10.1007/978-3-319-47829-6_1018-2, DOI: https://doi.org/10.1007/978-3-319-47829-6_1018-2, eBook Packages: Springer Reference Behavioral Science and PsychologyReference Module Humanities and Social Sciences, DOI: https://doi.org/10.1007/978-3-319-47829-6_1018-1, Over 10 million scientific documents at your fingertips, Not logged in Sharks/relatives also have an enlarged liver (up to 20% of the weight of the fish) that produces lots of oil. Morphology of the mechanosensory lateral line system in elasmobranch fishes: Ecological and behavioral considerations. Enrolling in a course lets you earn progress by passing quizzes and exams. Calcium deposits provide strength to the endoskeleton, which is composed of cartilage. (2022). CrossRef Boca Raton: CRC Press. [17][18] Shenacanthus vermiformis, which lived 436 million years ago, had thoracic armour plates resembling those of placoderms.[19]. What are the Economic Benefits of Chondrichthyes? The Journal of Physiology. Kardong, K. (2016). The midbrain (mesencephalon) itself is comprised of two optic lobes, which are especially well-developed in osteichthyes that hunt by sight. (Lond. Four pairs of gills are present including the operculum. The somatotopic organization of the olfactory bulb in elasmobranchs. However, many of their life history traits, such as low fecundity, the production of small numbers of highly precocious young, slow growth rates, and late maturity, make them highly . [5] They have several sensory organs which provide information to be processed. The egg cases of most species are more or less pillow-shaped; those of the horned sharks (Heterodontus francisci) are screw-shaped with a spiral flange. Electroreception, electrogenesis and electric signal evolution. Caputi, . The somatotopic organization of the olfactory bulb in elasmobranchs. A., & Demski, L. S. (2004). Circulatory System Part 2: The Heart and Major Vessels, Circulatory System Part 3: Blood Pressure, Circulatory System Part 4: Vessels, Capillary Fluid Exchange, Lymphatic System, The Respiratory System Part 1: Structures and Mechanisms of Breathing, The Respiratory System Part 2: Regulation of Breathing and Gas Exchange, The Nervous System: Part 1 Intro and the CNS, The Nervous System Part 3 Impulse Transmission, Nervous System Part 4: Peripheral Nervous System/Endocrine Control, Urinary System Part 3: Regulation of Urine Formation, Comparing reproductive methods in sharks [Video]. The modern bony fishes, class Osteichthyes, appeared in the late Silurian or early Devonian, about 416 million years ago. Die Parietalorgane. In this case, the egg is first coated in the shell gland with a temporary membranous capsule that lasts only during early development. A DiI-tracing study of the neural connections of the pineal organ in two elasmobranchs (Scyliorhinus canicula and Raja montagui) suggests a pineal projection to the midbrain GnRH-immunoreactive nucleus. Lisney, T. J., & Collin, S. P. (2007). They bring water into their bodies using one of two methods: Ram ventilation - requires forward movement by the organism. Journal of Experimental Biology, 207(20), 34633476. Vertebrate | Definition, Characteristics, Examples, Classification Visual Neuroscience, 26(4), 397. https://doi.org/10.1017/S0952523809990150. https://doi.org/10.1159/000100036. Christina graduated with a Master's in biology from the University of Louisiana at Lafayette. Growth is also measured by the statistical analysis of the length in systematically collected samples, by the space between concentric circles on the centra of the vertebrae, and by periodic measurements of specimens kept in aquariums. Cell and Tissue Research, 228(1), 139148. In this chapter we present a modern interpretation of the regional organization of the chondrichthyan brain mainly based on updated genoarchitectonic, neurochemical, and, in a lesser extent,. List of transitional fossils Chondrichthyes, Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date, "Function of the heterocercal tail in sharks: quantitative wake dynamics during steady horizontal swimming and vertical maneuvering", "Origin and evolution of the adaptive immune system: genetic events and selective pressures", "Sharks, rays and abortion: The prevalence of capture-induced parturition in elasmobranchs", "The diplacanthid fishes (Acanthodii, Diplacanthiformes, Diplacanthidae) from the Middle Devonian of Scotland", "Chondrichthyan-like scales from the Middle Ordovician of Australia", "The systematics of the Mongolepidida (Chondrichthyes) and the Ordovician origins of the clade", "Spiny chondrichthyan from the lower Silurian of South China", The oldest complete jawed vertebrates from the early Silurian of China - PubMed, "Jaws for a spiral-tooth whorl: CT images reveal novel adaptation and phylogeny in fossil Helicoprion", Images of many sharks, skates and rays on Morphbank, Myliobatiformes (stingrays and relatives), https://en.wikipedia.org/w/index.php?title=Chondrichthyes&oldid=1142043818, Short description is different from Wikidata, Articles with specifically marked weasel-worded phrases from August 2018, Creative Commons Attribution-ShareAlike License 3.0, This page was last edited on 28 February 2023, at 05:49. Journal of Fish Biology, 95(1), 92134. Brain, Behavior and Evolution, 69(4), 266279. ), Lehrbuch der vergleichenden mikroskopischen Anatomie der Wirbeltiere (pp. ), Biology of sharks and their relatives II (pp. https://doi.org/10.1007/BF00751027. (2001). Kajiura, S. M., Cornett, A. D., & Yopak, K. E. (2010). copyright 2003-2023 Study.com. I would definitely recommend Study.com to my colleagues. Odds are you are thinking of a member of the group Osteichthyes. Montgomery, J. C., Windsor, S., & Bassett, D. (2009). Characteristics of Chordata Reproduction | Study.com Environmental Biology of Fishes, 60(13), 4775. At the rostral, or nose, end of the fish lie olfactory lobes, which provide the sense of smell. ), Biology of sharks and their relatives (pp. The class can be divided into two subclasses; Elasmobranchii (sharks, rays, skates, and sawfish) and Holocephali (chimaeras). Chondrichthyes digestive system: The stomach, pharynx, mouth, intestines, and cloaca make up the digestive system. (1983). The class Chondrichthyes is divided into two subclasses: the Elasmobranchii (sharks, skates, and rays) and the Holocephali (elephant sharks and chimaeras). https://doi.org/10.1111/jfb.14068. This is a preview of subscription content, access via your institution. An Overview Of Pisces- Characteristics And Classifications - BYJUS Study fish brain anatomy. The first abundant genus of shark, Cladoselache, appeared in the oceans during the Devonian Period. Many of these structures are important for secreting hormones or acting as relay centers which transfer messages to different parts of the brain; for example, the pineal body helps fishes to detect light and dark. https://doi.org/10.1007/s004410000328. https://doi.org/10.1002/jmor.20106. The nervous system in fishes can be divided into two parts: the central nervous system and the peripheral nervous system. The fossil record of the Holocephali starts in the Devonian period. Describe how the Ampullae of Lorenzini helps Chondrichthyans navigate and migrate. 349402). Sensory biology of elasmobranchs. The General Characteristics of Chondrichthyes and Osteichthyes. Can grow up to 7.3m (24ft) and more than 1,400kg (3,100lb). Boca Raton: CRC Press. The skeleton is cartilaginous. Their skull contains a brain, which connects at the base of the skull to a spinal cord. praeside Arvid. The Wolffian ducts in males and Mullerian ducts in females become the functional urogenital ducts. This is most likely a secondary evolved characteristic, which means there is not necessarily a connection between the teeth and the original dermal scales. Brown, B. R. (2003). Environmental Biology of Fishes, 28(14), 3375. Also, they have very powerful nostrils and olfactory organs. Vertebrates comparative anatomy, function, evolution, 7th edn. This means that fish are capable of feeling stimuli related to pain. https://doi.org/10.1023/A:1007647924559. flashcard set. Their nervous system adaptations range from the wild and electric, to the generalized lateral line system that helps their entire body function like an ear. Cartilaginous fish have the following characteristics: Among the Chondrichthyes are powerful jaws that are found in marine fish. Discuss how osteichthyes sense their environment. Reproduction and Development in Chondrichthyan Fishes American Museum Novitates, 2017(3875), 115. https://doi.org/10.1016/j.jphysparis.2008.10.005. 1254). Osteichthyes are fishes that are often referred to as "bony fish". Chondrichthyes are jawed vertebrates with paired fins, paired nares, scales, and a heart with its chambers in series. They differ from Chondrichthyes, which have a skeleton composed largely of cartilage. Boca Raton: CRC Press. Protected by the shell and nourished by the abundant yolk, the embryo of an oviparous species develops for 18 to 59 weeks before hatching. They have a complex nervous system with a brain that connects to a spinal chord. Journal of Morphology, 269(11), 13651386. The principle component of shark liver oil is called squalene. By the start of the Early Devonian, 419 million years ago, jawed fishes had divided into three distinct groups: the now extinct placoderms (a paraphyletic assemblage of ancient armoured fishes), the bony fishes, and the clade that includes spiny sharks and early cartilaginous fish. Unusual features of the reproductive system include an epigonal organ in males and females. A review of the sensory biology of chimaeroid fishes (Chondrichthyes; Holocephali). https://doi.org/10.1007/BF00206272. Web the chondrichthyes are the cartilaginous fishes, such as sharks and rays, while the osteichthyes are the bony fishes. Mother produces up to 50 pups in each of two uteruses. Agnatha also have a peripheral nervous system which includes cranial nerves and spinal nerves. PPT - Class Chondrichthyes PowerPoint Presentation, free download - ID Brain, Behavior and Evolution, 69(4), 266279. Maisey, J. G., Miller, R., Pradel, A., Denton, J. S., Bronson, A., & Janvier, P. (2017). Just like humans and most vertebrates, bony fish have a nervous system comprised of a central brain and spinal cord, as well as many branching nerves. Do fishes have a nervous system? In the local market, scaleless species' skins are used for drumheads, while scaly species' skins are made into shagreen, Cell of Nervous System and Nerve Impulse Conduction for NEET, GERD Symptoms Important Concepts and Tips for NEET, Chinkara Important Concepts and Tips for NEET, Endocytosis - Important Concepts and Tips for NEET, Hibiscus - Important Concepts and Tips for NEET, Regulation of Kidney Function Important Concepts and Tips for NEET, NEET Biology Important Topics and Chapter Weightage, Find Best Teacher for Online Tuition on Vedantu. The hindbrain connects to the spinal cord via the myelencephalon, which functions in osmoregulation - water balance - and respiration. Remarks on the inner ear of elasmobranchs and its interpretation from skeletal labyrinth morphology. (2010). Chondrichthyans have a closed circulatory system. Sensory physiology and behavior of elasmobranchs. The relation of inner ear structure to the feeding behavior in sharks and rays. 14 Questions About Aquatic Animals Answered. Lateral lines in some species contain electroreceptors, which can detect electric signals in water generated by other organisms. The majority of sharks and rays other than the skates are ovoviviparous (that is, the egg hatches within the mother). In A. Oppel (Ed. As they do not have bone marrow, red blood cells are produced in the spleen and special tissue around the gonads. In J. C. Carrier, J. The next time you see a fish swimming in a fish tank, go off on a fishing trip, or visit an aquarium, think about the truly remarkable adaptations of the nervous system of the bony fish - the Osteichthyes. 304 lessons Each clasper has a groove for guidance of sperm. Systematic Ichthyology Laboratory, Department of Zoology, University of Braslia, Braslia, Brazil, Fauna and Protected Areas Laboratory, Department of Forest Engineering, University of Braslia, Braslia, Brazil, Laboratory of Vertebrate Comparative Anatomy, Department of Zoology, University of Braslia, Braslia, Brazil, Laboratory of Ichthyology, Department of Zoology, University of So Paulo, So Paulo, Brazil, You can also search for this author in The first Cartilaginous fishes evolved from Doliodus-like spiny shark ancestors. A distinct heart, anteroventral to the liver, is enclosed in a pericardial sac. 2023 Springer Nature Switzerland AG. https://doi.org/10.1038/421495a. 2023 Springer Nature Switzerland AG. They may be the remains of stem-chondrichthyans, but their classification remains uncertain. Reviews in Fish Biology and Fisheries, 20(4), 571590. Journal of Physiology-Paris, 102(46), 256271. Manta Ray. Most of them live in the ocean. We've learned that they have a branching system of peripheral nerves that help them sense their environment, as well as motor nerves that help them move. Fun fact: Sharks can use their ampullae to navigate the globe by tracking earths electromagnetic field. They are also produced in the Leydig's organ, which is only found in certain cartilaginous fishes. that the original bony plates of all vertebrates are now gone and that the present scales are just modified teeth, even if both the teeth and body armor had a common origin a long time ago. Afferent signals come from muscles, sensory organs, and structures to provide information to the central nervous system. According to the structure of the endoskeleton, Pisces has two types of classes: the Chondrichthyes and the Osteichthyes. https://doi.org/10.1111/jfb.13922. Visual Neuroscience, 26(4), 397. https://doi.org/10.1017/S0952523809990150. Boca Raton: CRC Press. https://doi.org/10.1007/s00429-014-0705-0. Which one is exclusive to this class? CrossRef Maruska, K. P. (2001). Two chambered hearts, one with an auricle and one with a ventricle, are present in these creatures. https://doi.org/10.1038/421495a. Question: Why would a shark a free swimming fish want to produce a lot of oil? Veronica Slobodian . Chondrichthyans have tooth-like scales called dermal denticles or placoid scales. Systematic Ichthyology Laboratory, Department of Zoology, University of Braslia, Braslia, Brazil, Fauna and Protected Areas Laboratory, Department of Forest Engineering, University of Braslia, Braslia, Brazil, Laboratory of Vertebrate Comparative Anatomy, Department of Zoology, University of Braslia, Braslia, Brazil, Laboratory of Ichthyology, Department of Zoology, University of So Paulo, So Paulo, Brazil, You can also search for this author in They have a two chambered heart in which the blood enters the heart through the vein and exits through a vein on its way to the gills. Anyone you share the following link with will be able to read this content: Sorry, a shareable link is not currently available for this article. BHL Collections: Observationes in anatomiam chondropterygiorum praecipue Squali et Rajae generum : quas venia . This is a form of asexual reproduction in which an embryo develops without being fertilized. Sensory biology of elasmobranchs. With the exception of some who are able to breathe . CrossRef Google Scholar Gruber SH (1977) The visual system of sharks; adaptations and capability. Test of the mechanotactile hypothesis: Neuromast morphology and response dynamics of mechanosensory lateral line primary afferents in the stingray. She is a current PhD student in biology at Wake Forest University, and has been teaching undergraduate students biology for the last three years. The peripheral nervous system contains the many nerves that extend from the brain and spinal cord and articulate with other structures in the body. Some lay eggs on the bottom and the baby sharks (pups) develop in a, Get nutrients from umbilical cord (like humans), Mother produces eggs (like oviparous system). However, there is currently no evidence of this. In J. C. Carrier, J. Provided by the Springer Nature SharedIt content-sharing initiative, Over 10 million scientific documents at your fingertips, Not logged in The disk of the eastern Pacific round stingray (Urolophus halleri) increases in width on the average from 75 mm (3 inches) at birth to 150 mm (6 inches) when mature (that is, at 2.6 years old). https://doi.org/10.1002/jmor.1068. Unit 2-3: Mechanisms of Evolution and Natural Selection, Unit 3a-1: Genetic Modification and Gene Transfer, Unit 5-3: Phylum Platyhelminthes Webquest Notes, Unit 5-4: Phylum Nematoda Webquest Notes. https://doi.org/10.1242/jeb.01140. Both freshwater and marine species fall into these classes. As with all fish, sharks/relatives have a lateral line, which gives them a sixth sense to detect vibrations in water. Crampton, W. G. R. (2019). https://doi.org/10.1007/BF00206272. In J. Chondrichthyes- Introduction, Classification, Examples and Characteristics Electroreception in marine fishes: Chondrichthyans. Electroreceptors are organs that detect electric signals in water and are found on the lateral line running down the side of a fish. They have several sensory organs which provide information to be processed. In O. M. Johari (Ed. All studies indicate a slow growth rate. In O. M. Johari (Ed. Several shark species are viviparousthat is, the yolk sac develops folds and projections that interdigitate with corresponding folds of the uterine wall, thus forming a yolk-sac placenta through which nutrient material is passed from the mother. Chondrichthyes: (Cartilaginous Fish-Sharks, Rays, and Skates Births live young that lived off a yolk sac inside an egg. Nutrients supplied by blood vessels. (1983). The traditional groups include Agnatha, Chondrichthyes, Osteichthyes, Amphibia, Reptilia, Aves, and Mammalia. A., Castell, M. E., Aguilera, P. A., Pereira, C., Nogueira, J., Rodrguez-Cattaneo, A., & Lezcano, C. (2008). Journal of Morphology, 250(3), 236264. Despite several recent findings regarding the relationships of early chondrichthyans (see Maisey et al. However, Chondrichthyans also have special sensing organs called the Ampullae of Lorenzini giving them a seventh sense., Figure 4: Close up of a shark rostum notice the series of dots scatter throughout. Comparative Vertebrate Physiology Long Answer Test Review! (2009). An egg of the whale shark found in the Gulf of Mexico measured 30 cm (12 inches) long by about 14 cm (5.5 inches) wide and was 8 cm (3 inches) thick. 393434). The neuroecology of cartilaginous fishes: sensory strategies for [4], Like all other jawed vertebrates, members of Chondrichthyes have an adaptive immune system.[5]. Starfish, on the other hand, still maintain a nervous system but lack a true brain. Vertebrates are grouped based on anatomical and physiological traits. 6. ), Biology of sharks and their relatives (pp. Hart, N. S. (2020). https://doi.org/10.1111/jfb.13922. There are so many misconceptions about this class of vertebrates; education is the first step to protecting sharks which in turn will help protect food webs and biodiversity in our oceans. Morphology of the mechanosensory lateral line system in elasmobranch fishes: Ecological and behavioral considerations. Explain how a shark is able to maintain buoyancy. https://doi.org/10.1206/3875.1. They are oviparous in some cases and viviparous in others. Encyclopedia of Animal Cognition and Behavior, https://doi.org/10.1007/978-3-319-55065-7_1018, Shipping restrictions may apply, check to see if you are impacted, https://doi.org/10.1016/j.jphysparis.2008.10.005, https://doi.org/10.1016/j.semcdb.2020.03.012, https://doi.org/10.1111/j.1095-8649.2011.03214.x, https://doi.org/10.1007/s11160-010-9162-x, https://doi.org/10.1017/S0952523809990150, https://doi.org/10.1113/jphysiol.1951.sp004638, https://doi.org/10.1111/j.1749-4877.2008.00130.x, https://doi.org/10.1007/s00429-014-0705-0, Reference Module Humanities and Social Sciences, Tax calculation will be finalised during checkout. The nervous system is composed of neural tissue which works by reacting to stimuli and sending responses via electric signals. Write down the characteristics of Cartilaginous Fish. The pineal organ of Raja clavata: Opsin immunoreactivity and ultrastructure. Producing an electric signal is a specialization in the nervous system of some Osteichthyes. Endocrine system | Definition, Organs, Function, Structure, Diagram Academic Press. This lesson will discuss the nervous system of fishes in more detail, including the anatomy of the fish nervous system, how fish brain anatomy compares to that of a human, and the two components of a fish's nervous system. Fish contain pain receptors called nociceptors like humans do. Phylogenetic systematics of extant chimaeroid fishes (Holocephali, Chimaeroidei). Do fishes have nerves in their mouth, tail, or fins? With the mouth closed, they contract the bucco-pharyngeal cavity while dilating the gill pouches, thus drawing the water over the gills where the exchange of oxygen and carbon dioxide takes place. Include what previous structure the jaw is thought to have evolved from. By its 22nd year, it is estimated to be approaching its maximum length of 1.6 metres (about 5 feet). People living in coastal regions of many developing countries rely heavily on them for income and employment. (Lond. Class Chondricthyes - 7 Vertebrates The Osteichthyes Respiratory System. Nature, 421(6922), 495495. Subjects: Anatomy Araripe Plateau Brazil Cear (State) Chondrichthyes Cretaceous Egertonodus basanus Fishes, Fossil Neuroanatomy Paleontology Phylogeny Sharks Sharks, Fossil Skull . Hueter, R. E., Mann, D. A., Maruska, K. P., Sisneros, J. https://doi.org/10.1016/j.semcdb.2020.03.012. These are the same parts that are observed in humans.