In contrast, people and other jawed vertebrates brandish adaptive immune systems. |
|
In insects, as in all arthropods, the main nerve cord lies ventrally, rather than dorsally as in vertebrates. |
|
Their eggs are large, green, and poisonous to warm-blooded vertebrates, including humans. |
|
You can find this same remarkable system in humans, albatrosses, rattlesnakes, bullfrogs, and all other land vertebrates. |
|
One of the most prominent characteristics of early vertebrates is the elongate caudal fin bearing fin rays. |
|
In modern classification schemes, living vertebrates consist of two main groups, the jawless Agnatha and the jawed Gnathostomata. |
|
By the mid 1970s, insulin had been isolated and sequenced from all classes of vertebrates, including Agnatha. |
|
The earliest fossil vertebrates belong to a group called the Agnatha or jawless vertebrates. |
|
Modern vertebrates are classified into two major groups, the gnathostomes and the agnathans. |
|
The repeated appearance of higher grades was true long before primates, before mammals, or any vertebrates. |
|
In terrestrial vertebrates, otoconia are found in three inner-ear sensors, the saccule, the utricle, and the lagena. |
|
Litman next plans to look for novel immune genes in jawless vertebrates, such as lamprey and hagfish. |
|
Sure enough, lampreys are simple vertebrates lacking jaws, teeth and a bony skeleton, whereas sharks are much more complex animals. |
|
Among vertebrates, newts and other urodele amphibians show a remarkable capacity for regeneration. |
|
Unlike all other jawed vertebrates, placoderms never had teeth, and did not descend from toothed ancestors. |
|
For example, it is possible that the brainstem reticular formation is divided into the same number of nuclei in all jawed vertebrates. |
|
In vertebrates, it looks like the ground state is to make ribby thoracic segments everywhere. |
|
This is unfortunate because the skeletal reorganization experienced by anurans during metamorphosis is unparalleled among vertebrates. |
|
As in other vertebrates, the anuran auditory system is susceptible to noise masking. |
|
The first vertebrates to evolve true flight were the pterosaurs, flying archosaurian reptiles. |
|
|
Among vertebrates, only the cartilaginous fishes, lungfishes and amphibians possess exceptionally large C-values. |
|
Today lungs are found not only in land vertebrates but also in a few obscure fish lineages, such as gar, bichir, and lungfish. |
|
However, the primary axis of cnidarians lacks the degree of axial differentiation found in vertebrates or insects. |
|
The body axis of vertebrates is an integrated cylinder of bones, connective tissue, and muscle. |
|
Pterosaurs were the first vertebrates, or animals with backbones, to flap their wings and fly. |
|
Both chickens and humans are vertebrates, a group of animals that have skulls and backbones. |
|
Such cases of female competition and aggression have been noted in many birds and other vertebrates. |
|
The emergence of terrestrial vertebrates from fish in the Late Devonian was one of the most significant events in the history of life. |
|
They probably subsisted on insects and other small terrestrial invertebrates and perhaps even on small vertebrates. |
|
All these taxa are relevant to the history of the conquest of land by vertebrates because they are outside the large clades of extant tetrapods. |
|
Before tetrapods existed, vertebrates were all confined to living in aquatic habitats. |
|
The sea urchin occupies an important evolutionary position with respect to vertebrates and humans. |
|
Such segmentally repeated functional groups may be present throughout vertebrates since all vertebrate brains are segmented. |
|
Our focus on hindbrain was motivated by the observation that the hindbrains of all vertebrates are segmentally organized. |
|
They were lightly built and were probably opportunistic feeders, eating insects as well as small vertebrates. |
|
Amphibians are regarded as sentinel vertebrates in the current drama of global extinctions. |
|
In vertebrates, the limb apical epidermis promotes proliferation and inhibits differentiation of underlying mesenchymal cells. |
|
Thus the mesofauna represent an important trophic link of the detritus food chain to terrestrial vertebrates. |
|
Color changing or metachromatism or metachrosis is common in chordates and in vertebrates such as fish, amphibians and in some types of lizards. |
|
In the vertebrates the metamere is evident in the embryonic stages and tends to disappear in the adults. |
|
|
In most vertebrates the hyoid supports the tongue, as it does in the snake-necked turtle. |
|
In nonmammalian vertebrates, tooth replacement is intimately related to growth. |
|
Preliminary results show that molas, unlike other large marine vertebrates, are mostly home bodies and unlikely to make large-scale migrations. |
|
Mammals are the only major group of vertebrates in which mothers are more involved. |
|
These creatures are prey to vertebrates like birds, mouse opossums, salamanders, and frogs. |
|
The complementary question to be asked is why muscle modulation seems so unimportant in skeletal muscles of vertebrates. |
|
Man and most vertebrates are characterized by an internal rather than an external skeleton. |
|
This overall morphological simplicity, in theory, makes tadpoles good models for exploring how vertebrates control undulatory movements. |
|
In vertebrates finally, the organization of muscles into myotomes for swimming has long been considered of crucial adaptative importance. |
|
As is the condition in other unisexual vertebrates, the silver crucian carp probably has a hybridization origin. |
|
Fish are vertebrates, with a brain, a central nervous system and pain receptors all over their bodies, including the lips. |
|
Unlike land vertebrates or marine mammals, fish don't have lungs, but they do have paired respiratory structures called gills, or branchia. |
|
Comparable studies of fishes and other aquatic vertebrates are scarce, despite a wealth of neontological data. |
|
The functional unit in the kidney of all vertebrates is the uriniferous tubule comprising a nephron and a collecting tubule. |
|
Chordates are divided into urochordates, cephalochordates, and vertebrates. |
|
The new additions double the number of known venomous vertebrates to more than 2,000 species. |
|
In short, this analysis finds that conodonts are more derived than any of the living jawless vertebrates. |
|
Their presence suggests the feature appeared in a common ancestor of jawed vertebrates, or gnathostomes. |
|
But some land vertebrates have lost some or all of their ability to detect pheromones. |
|
No one had unambiguously located such genes in animals more primitive than the jawed vertebrates. |
|
|
The limbs of tetrapod vertebrates evolved from fins, with the digits as a novel feature. |
|
For that reason the earliest terrestrial vertebrates did not come equipped with an occiput, as we understand the term. |
|
Such a growth trajectory is uncommon or unreported among terrestrial vertebrates and merits closer examination. |
|
When the fossilized lamprey lived, there were probably many types of jawless vertebrates. |
|
Following Simpson, Newell mentioned the example of the relatively wider limb bones of larger land vertebrates. |
|
The temperature at which the eggs of ectothermic vertebrates incubate can influence several phenotypic traits of offspring. |
|
Floras and faunas from these beds have been discussed, but the remains of small vertebrates have received little attention. |
|
Instead the molecules that orchestrate adaptive immunity are found in the jawed vertebrates and nowhere else. |
|
Frugivorous vertebrates ingest fruits and the seeds within, later defecating the seeds. |
|
If you look at all the warm-blooded vertebrates, we've all got roughly the same life span. |
|
The third puzzle is why all of this should happen in warm-blooded vertebrates but not in cold-blooded vertebrates. |
|
In southern Arizona the most common vertebrates found in bullfrogs are other bullfrogs, Schwalbe said. |
|
These so-called virgin births are common in invertebrates like snails, but are unusual in higher vertebrates. |
|
The circulatory systems of other vertebrates, as well as those of squids and octopuses, employ similar rubbery materials. |
|
Eggs and hatchlings are predated by members of every class of vertebrates and numerous invertebrates. |
|
Megapodes are omnivores, known to eat plant material, invertebrates and small vertebrates. |
|
The neural retina of zebrafish, as in other vertebrates, arises from cells that line the optic cup. |
|
Natriuretic peptides are a group of hormones playing important roles in cardiovascular and osmoregulatory systems in vertebrates. |
|
Enamel, or enameloid tissue covering tubercles, was clearly described in Ordovician vertebrates such as the ostracoderms. |
|
Marine vertebrates including tunas, seabirds, sharks, sea turtles, pinnipeds and cetaceans use a pelagic ecosystem we barely understand. |
|
|
The forelimbs and hindlimbs of vertebrates arise at precise positions along the antero-posterior axis of the body. |
|
In more basal vertebrates, cartilaginous structures can become superficially calcified in at least two different modes. |
|
However, there is little evidence to show whether melanocytes in homeothermal vertebrates respond to visible light or not. |
|
In their circulatory, excretory, and endocrine functions, vertebrates differ markedly from other animals. |
|
Hb is present in all vertebrates investigated so far, with the exception of some icefish species. |
|
Nevertheless, it is unusual among vertebrates for the pelvis to play an active role in inspiration. |
|
Nevertheless, there were no significantly supported clusters including molecules from both vertebrates and invertebrates. |
|
This perciform fish family is one of the most species-rich families of vertebrates with at least 1,300 and perhaps as many as 1,870 species. |
|
Electrical synapses couple the electrical activity of neurons in central and peripheral nervous systems of vertebrates and invertebrates. |
|
The future of experiments to test the behavioral role of neurons in vertebrates lies in using reverse genetic tools to perturb function. |
|
In the case of the retina and the pineal of lower vertebrates, the cells involved are direct photoreceptors. |
|
Melatonin and serotonin are indoleamines derived from tryptophan which are produced by the pineal gland in vertebrates. |
|
Well documented in vertebrates, this so-called selfish herd effect has now been reported for an invertebrate, the fiddler crab. |
|
Parasitism is a common phenomenon in many animal taxa, from simple platyhelminths to vertebrates such as fish and birds. |
|
Included among these vertebrates are sharks, bony fishes, amphibians, turtles, lizards, crocodiles, and dinosaurs. |
|
Marine vertebrates included the large dolphin-like ichthyosaurs and the long-necked plesiosaurs, marine crocodiles, turtles, and other reptiles. |
|
These distinctions correspond closely to our distinction between vertebrates and invertebrates. |
|
While studies have been done in mammals and other vertebrates less is known of invertebrates. |
|
Smaller vertebrates and invertebrates are also known in abundance from France and Bavaria. |
|
It is typical of vertebrates but rare among invertebrates, being seen in a few molluscs and arachnids. |
|
|
Echinoderms are considered the invertebrate group most closely related to the vertebrates. |
|
While ubiquitous among vertebrates, it occurs less frequently in invertebrate phyla. |
|
The relationships between hagfishes, lampreys, and jawed vertebrates are one of the still-unresolved problems in craniate phylogeny. |
|
In this organism crossing over between X and Y chromosomes was shown for the first time in vertebrates. |
|
Accordingly, the hypothesized deterrence of ethanol to frugivorous vertebrates, or specifically primates, is unsubstantiated. |
|
Furthermore, fruits in the temperate zone are typically removed by frugivorous vertebrates before they become damaged or show signs of rot. |
|
In the adults of most vertebrates, the braincase is largely fused into a single solid mass. |
|
Mammalian vertebrates may also have the morphological equivalent of the septate junction where Schwann cells link to nerve axons at the node of Ranvier. |
|
Owen's studies on fossil vertebrates were immensely productive. |
|
Basically what is available in the fossil record are only hard parts-bones and teeth for vertebrates, and shells for mollusks, arthropods and echinoderms. |
|
Expression is also detected variously in visceral endoderm, and anterior mesoderm and endoderm of the gut and pharynx in some vertebrates and amphioxus. |
|
Human beings, in common with other vertebrates, possess a set of sense organs that provide information to the brain concerning orientation and motion of the body. |
|
In bony vertebrates, endochondral bones form from centers of ossification in the chondrocranium, although much of the braincase often remains cartilage. |
|
This is likely to be still less problematic for nonmammalian vertebrates. |
|
Jawed vertebrates appeared 100 million years later, in the Silurian. |
|
The first tetrapods, or land-living vertebrates, appeared during the Devonian, as did the first terrestrial arthropods, including wingless insects and the earliest arachnids. |
|
The history of vertebrates based on the paleontological evidence has not been substantially changed in its broadscale pattern since the 19th century. |
|
The amniotes are a monophyletic group of vertebrates, comprising reptiles, birds, and mammals, that develops in its embryonic life the envelope called amnion. |
|
The degree of completeness of the combinatorial system in the most anciently arisen living vertebrates to possess the combinatorial immune response was surprising. |
|
And while jawless vertebrates were present in the Cambrian, it was not until the Ordovician that armored fish became common enough to leave a rich fossil record. |
|
|
The phylogenic analysis implies that the multiple actinin isoforms found in modern vertebrates arose after the divergence of the vertebrate and urochordate lineages. |
|
The color yellow in the animal world comes from pigments called carotenoids, which vertebrates cannot synthesize and must therefore obtain directly from their diets. |
|
As early vertebrates grew larger and developed bony scales or plates between their tissues and the water, they developed gills for taking up oxygen from the water. |
|
It seems that they don't know that the first vertebrates were fish. |
|
The hagfish, together with lampreys, are living representatives of the jawless vertebrates and are considered to be the most evolutionarily ancient vertebrates. |
|
Amphioxus is the closest living invertebrate relative of the vertebrates, and is key to understanding the evolution of vertebrates from an invertebrate ancestor. |
|
Many ripe fleshy fruits whose primary function is to attract seed dispersers also contain unpleasant chemicals that deter consumption by vertebrates. |
|
Some 450 million years ago, both jawed and jawless vertebrates began relying on cells called lymphocytes to support the burgeoning adaptive immune system. |
|
The history of the epibranchials presumably begins wherever vertebrates first developed a jointed, internal branchial arch rather than an unjointed, external branchial basket. |
|
The fate maps of the different vertebrates are thus similar when one looks at the relationship between the germ layers and the site of ingression of cells at gastrulation. |
|
In the evolution of vertebrates, long bodies with continuously flexible notochords and segmental muscles existed before the appearance of segmental vertebrae. |
|
These first vertebrates lacked jaws, like the living hagfish and lampreys. |
|
The organogenesis and the final structure of the cephalopod eye fundamentally differ from those of vertebrates such as humans. |
|
These evolutionary modifications make the spine more flexible but weaker than the spines of terrestrial vertebrates. |
|
Therapsids and archosaurs were the chief terrestrial vertebrates during this time. |
|
The special adaptations of reptiles enabled them to flourish in the drier climate of the Permian and they grew to dominate the vertebrates. |
|
The oceans were inhabited by marine reptiles such as ichthyosaurs and plesiosaurs, while pterosaurs were the dominant flying vertebrates. |
|
A reported 33,400 species of fish, including bony and cartilaginous fish, had been described by 2016, more than all other vertebrates combined. |
|
Ambulocetus probably lived in mangroves in brackish water and fed in the riparian zone as a predator of fish and other vertebrates. |
|
With 33,600 described species, fish exhibit greater species diversity than any other group of vertebrates. |
|
|
The diversity of jawed vertebrates may indicate the evolutionary advantage of a jawed mouth. |
|
Fish eyes are similar to those of terrestrial vertebrates like birds and mammals, but have a more spherical lens. |
|
Different bat species have different diets including insects, nectar, pollen, fruit and even vertebrates. |
|
Some bats prey on vertebrates, such as fish, frogs, lizards, birds and mammals. |
|
Kestrels feed chiefly on terrestrial vertebrates and invertebrates of appropriate size, such as rodents, reptiles, or insects. |
|
Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. |
|
Lizards make use of their senses of sight, touch, olfaction and hearing like other vertebrates. |
|
Aquatic vertebrates must obtain oxygen to survive, and they do so in various ways. |
|
Birds, at over 10,000 living species, are the most diverse group of vertebrates besides perciform fish. |
|
Dinosaurs were the dominant terrestrial vertebrates of the Mesozoic, especially the Jurassic and Cretaceous periods. |
|
It is replete with the mollusks, the vertebrates, the echinoderms, the brachiopods and some groups of arthropods. |
|
This has resulted in empty forests, ecological communities depleted of large vertebrates. |
|
Given a warmer climate, the diversity of organisms is also higher, since there are about 850 plant species and 280 vertebrates species. |
|
The spores are rich in lipids, protein and calories, so some vertebrates eat these. |
|
The vertebral arch surrounds the spinal cord, and is of broadly similar form to that found in most other vertebrates. |
|
Lampreys have vertebral arches, but nothing resembling the vertebral bodies found in all higher vertebrates. |
|
The venoms of some vermivorous species contain proteolytic enzymes which cause local necrosis at the site of injection in vertebrates. |
|
Chytrid fungi are common pathogens of plants and insects but had never before been known to attack vertebrates. |
|
This primitive arrangement of chondrocranium and gill arches forms the basis of the skull in all jawed vertebrates. |
|
During the Jurassic period, the primary vertebrates living in the sea were fish and marine reptiles. |
|
|
Mouth is without jaws in lampreys and hagfishes and bounded by jaws in all other vertebrates. |
|
Cementum is the least known calcified tissue in vertebrates and several questions about cementogenesis have not yet been answered. |
|
The first vertebrates appeared in the form of primitive fish, which greatly diversified in the Silurian and Devonian Periods. |
|
In many vertebrates, the neurenteric canal connects the medullary tube and the primitive intestine. |
|
Others consider them a sister group of vertebrates in the common taxon of craniata. |
|
However, a few vertebrates have secondarily lost this anatomy, retaining the notochord into adulthood, such as the sturgeon and coelacanth. |
|
The central nervous system of vertebrates is based on a hollow nerve cord running along the length of the animal. |
|
Of particular importance and unique to vertebrates is the presence of neural crest cells. |
|
The vertebrates are the only chordate group to exhibit cephalisation, the concentration of brain functions in the head. |
|
All of these early vertebrates lacked jaws in the common sense and relied on filter feeding close to the seabed. |
|
Other ways of classifying the vertebrates have been devised, particularly with emphasis on the phylogeny of early amphibians and reptiles. |
|
Boars may occasionally prey on small vertebrates like newborn deer fawns, leporids and galliform chicks. |
|
Vertebrate paleontology concentrates on fossils of vertebrates, from the earliest fish to the immediate ancestors of modern mammals. |
|
Fish, the world's first true vertebrates, continued to evolve, and those with jaws may have first appeared late in the period. |
|
Birds of prey generally prey on vertebrates, which are usually quite large relative to the size of the bird. |
|
Unlike vertebrates, insects do not generally carry oxygen in their haemolymph. |
|
This has led to the conclusion that invertebrates are a group that deviates from the normal, vertebrates. |
|
It is also possible that some humans believe that, they themselves being vertebrates, the group deserves more attention than invertebrates. |
|
Despite the names, the small and large intestines of sea urchins are in no way homologous to the similarly named structures in vertebrates. |
|
Importantly, urchins act as the closest living relative to chordates and thus may shed light on the evolution of vertebrates. |
|
|
As jellyfish are not true fish, which are vertebrates, the word jellyfish is considered by some to be a misnomer. |
|
Species complexes occur in insects such as Heliconius butterflies, vertebrates such as Hypsiboas treefrogs, and fungi such as the fly agaric. |
|
The first level designates the basic subdivisions of fossil procaryotes, Single-Celled eucaryotes, invertebrates, vertebrates, and plants. |
|
Called placoderms, these extinct animals were among the earliest vertebrates with jaws. |
|
The primary hosts for Rickettsia species are arthropods that can also act as disease vectors for humans and other vertebrates. |
|
Ranaviruses are emerging infections in ectothermic and poikilothermic vertebrates. |
|
There is much interest in these deep sea hemichordates since they are close to the evolutionary link between vertebrates and invertebrates. |
|
Consider the urodeles, a class of vertebrates that includes newts and salamanders. |
|
Later, sharks and bony fish lost the muscles and then early four-limbed vertebrates that moved onto land independently evolved them. |
|
Effect of menthol on two types of Ca currents in cultured sensory neurones of vertebrates. |
|
Ranaviruses are emerging pathogens of ectothermic vertebrates with a global distribution. |
|
Fossil vertebrates have been known from the Miocene of east Texas for over 100 years. |
|
Of course, eyes are characteristic of the vertebrates in the deuterostome group. |
|
The coronary arteries start in the right and left aortic sinus and provide blood to the heart muscle in a similar fashion to most other vertebrates. |
|
Therapsids, a group of synapsids, descended from pelycosaurs in the Middle Permian, about 265 million years ago, and became the dominant land vertebrates. |
|
In 1894, marine biologist Walter Garstang suggested that the primitive ciliary band, which harbors neurons, evolved into the dorsal nerve cord of vertebrates. |
|
The cardinal tetra is one of the most abundant vertebrates in the Amazon. |
|
Indeed, lanternfish are among the most widely distributed, populous, and diverse of all vertebrates, playing an important ecological role as prey for larger organisms. |
|
Many other animals such as the vertebrates, display similar rhythms. |
|
Various noninsect arthropods are eaten, as are molluscs and crustaceans where available, earthworms, and even vertebrates such as lizards and frogs. |
|
|
The vertebrates traditionally include the hagfish, which do not have proper vertebrae due to their loss in evolution, though their closest living relatives, the lampreys, do. |
|
However, unlike most vertebrates, lobsters express telomerase as adults through most tissue, which has been suggested to be related to their longevity. |
|
Postcranial pneumaticity is absent in all other extant vertebrates with the known exceptions of osteoglossomorph fish and the hyoid bone in howler monkeys. |
|
Amphibians were the dominant land vertebrates, of which one branch would eventually evolve into amniotes, the first solely terrestrial vertebrates. |
|
Could it be that the ancestor of the deuterostomes was a bottom-feeding dweller in the dark? Of course, eyes are characteristic of the vertebrates in the deuterostome group. |
|
All known species develop in invertebrates, especially insects, but the larvae are capable of encysting in a wide range of animals, including vertebrates. |
|
One archosaur group, the dinosaurs, were the dominant land vertebrates for the rest of the Mesozoic, and birds evolved from one group of dinosaurs. |
|
During the slow recovery from this catastrophe a previously obscure group, archosaurs, became the most abundant and diverse terrestrial vertebrates. |
|
The extinctions were apparently fairly sudden, at least among vertebrates. |
|
Today, the only jawless vertebrates are lampreys and hagfishes, whereas jawed vertebrates number more than fifty thousand species, including ourselves. |
|
Conventional classification has living vertebrates grouped into seven classes based on traditional interpretations of gross anatomical and physiological traits. |
|
Supercooling and freeze-tolerance in the European wall lizard, Podarcis muralis, with a revisional history of the discovery of freeze-tolerance in vertebrates. |
|
Agnathan vertebrates in the Lower Silurian of Gotland, Sweden. |
|
The extinct Pikaia gracilens has been confirmed as the oldest known member of the chordate family, which includes all modern vertebrates including humans. |
|
This early tetrapod could be the earliest example of a reptile and explain the origin of amniotes, all vertebrates that belong to reptiles, birds and mammals. |
|
Turtles lack any such holes and so are the only living anapsids, a group that includes fossils of the most primitive vertebrates capable of living entirely on land. |
|
Quantifying the dose of an arbovirus transmitted by mosquitoes is essential for designing pathogenesis studies simulating natural infection of vertebrates. |
|
Hagfishes lack a true vertebral column, and are therefore not properly considered vertebrates, but a few tiny neural arches are present in the tail. |
|
In other vertebrates, the number of cervical vertebrae can range from a single vertebra in amphibians, to as many as 25 in swans or 76 in the extinct plesiosaur Elasmosaurus. |
|
Lymph hearts of lower vertebrates are propulsatile organs, whose main function is to pump the lymph from subcutaneous lymph sacs into the venous system. |
|
|
Molecular analysis since 1992 has suggested that hagfish are most closely related to lampreys, and so also are vertebrates in a monophyletic sense. |
|
Galicia has 262 inventoried species of vertebrates, including 12 species of freshwater fish, 15 amphibians, 24 reptiles, 152 birds, and 59 mammals. |
|