The Carboniferous is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period 358.9 Ma to the beginning of the Permian Period, 298.9 Ma. It is the fifth and penultimate period of the Paleozoic and the fifth period of the Phanerozoic. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian and the later Pennsylvanian.
The Pennsylvanian is, on the ICS geologic timescale, the younger of two subperiods of the Carboniferous Period. It lasted from roughly 323.2 million years ago to 298.9 million years ago. As with most other geochronologic units, the rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain by a few hundred thousand years. The Pennsylvanian is named after the U.S. state of Pennsylvania, where the coal beds of this age are widespread.
A gill is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are kept moist. The microscopic structure of a gill presents a large surface area to the external environment. Branchia is the zoologists' name for gills.
Odonata is an order of predatory flying insects that includes the dragonflies and damselflies. The two major groups are distinguished with dragonflies (Anisoptera) usually being bulkier with large compound eyes together and wings spread up or out at rest, while damselflies are usually more slender with eyes placed apart and wings folded together along body at rest. Adult odonates can land and perch, but rarely walk.
Aquatic insects or water insects live some portion of their life cycle in the water. They feed in the same ways as other insects. Some diving insects, such as predatory diving beetles, can hunt for food underwater where land-living insects cannot compete.
Arthropleuridea is an extinct subclass of myriapod arthropods that flourished during the Carboniferous period, having first arisen during the Silurian, and perishing in the Early Permian. Members are characterized by possessing diplosegement paranotal tergal lobes separated from the body axis by a suture, and by sclerotized plates buttressing the leg insertions. Despite their unique features, recent phylogenetic research suggests Arthropleuridea be included among millipedes in the class Diplopoda. The subclass contains three or two recognized orders, each with a single genus.
Meganisoptera is an extinct order of large dragonfly-like insects, informally known as griffenflies or (incorrectly) as giant dragonflies. The order was formerly named Protodonata, the "proto-Odonata", for their similar appearance and supposed relation to modern Odonata. They range in Palaeozoic times. Though most were only slightly larger than modern dragonflies, the order includes the largest known insect species, such as the late Carboniferous Meganeura monyi and the even larger early Permian Meganeuropsis permiana, with wingspans of up to 71 centimetres (28 in).
Arthropleura is a genus of massive millipedes that lived in what is now North America and Europe around 345 to 290 million years ago, from the Viséan stage of the lower Carboniferous Period to the Sakmarian stage of the lower Permian Period. The species of the genus are the largest known land invertebrates of all time, and would have had few, if any, predators.
The most recent understanding of the evolution of insects is based on studies of the following branches of science: molecular biology, insect morphology, paleontology, insect taxonomy, evolution, embryology, bioinformatics and scientific computing. It is estimated that the class of insects originated on Earth about 480 million years ago, in the Ordovician, at about the same time terrestrial plants appeared. Insects are thought to have evolved from a group of crustaceans. The first insects were landbound, but about 400 million years ago in the Devonian period one lineage of insects evolved flight, the first animals to do so. The oldest insect fossil has been proposed to be Rhyniognatha hirsti, estimated to be 400 million years old, but the insect identity of the fossil has been contested. Global climate conditions changed several times during the history of Earth, and along with it the diversity of insects. The Pterygotes underwent a major radiation in the Carboniferous while the Endopterygota underwent another major radiation in the Permian.
Coal forests were the vast swathes of swamps and riparian forests that covered much of the land on Earth's tropical regions during the late Carboniferous (Pennsylvanian) and Permian periods. As plant matter from these forests decayed, enormous deposits of peat accumulated, which later became buried and converted into coal over the subsequent eras.
A paleoatmosphere is an atmosphere, particularly that of Earth, at some unspecified time in the geological past.
This article attempts to place key plant innovations in a geological context. It concerns itself only with novel adaptations and events that had a major ecological significance, not those that are of solely anthropological interest. The timeline displays a graphical representation of the adaptations; the text attempts to explain the nature and robustness of the evidence.
Insects are hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body, three pairs of jointed legs, compound eyes, and a pair of antennae. Insects are the most diverse group of animals, with more than a million described species; they represent more than half of all animal species.
Although oxygen is the most abundant element in Earth's crust, due to its high reactivity it mostly exists in compound (oxide) forms such as water, carbon dioxide, iron oxides and silicates. Before photosynthesis evolved, Earth's atmosphere had no free diatomic elemental oxygen (O2). Small quantities of oxygen were released by geological and biological processes, but did not build up in the reducing atmosphere due to reactions with then-abundant reducing gases such as atmospheric methane and hydrogen sulfide and surface reductants such as ferrous iron.
The Carboniferous rainforest collapse (CRC) was a minor extinction event that occurred around 305 million years ago in the Carboniferous period. The event occurred at the end of the Moscovian and continued into the early Kasimovian stages of the Pennsylvanian.
An insect's respiratory system is the system with which it introduces respiratory gases to its interior and performs gas exchange.
A spiracle or stigma is the opening in the exoskeletons of insects, myriapods, velvet worms and many arachnids to allow air to enter the trachea. In the respiratory system of insects, the tracheal tubes primarily deliver oxygen directly into the animals' tissues. In most species the spiracles can be opened and closed in an efficient manner to admit air while reducing water loss. In various species, this is done by a wide range of mechanisms, such as elastic closure, and closer muscles surrounding the spiracle or kinking the tube. In some the muscle relaxes to open the spiracle, in others to close it. The closer muscle is controlled by the central nervous system, but can also react to localized chemical stimuli. Several aquatic insects have similar or alternative closing methods to prevent water from entering the trachea. The timing and duration of spiracle closures can affect the respiratory rates of the organism. Spiracles may also be surrounded by hairs to minimize bulk air movement around the opening, and thus minimize water loss.
Bojophlebia is an extinct genus of winged insect from the Pennsylvanian period of the Czech Republic. It includes only a single species, Bojophlebia prokopi, and is the only member of the family Bojophlebiidae. Bojophlebia prokopi was first described in 1985 by Jarmila Kukalová-Peck, who originally described it as a large mayfly-like insect. This original interpretation has since been rejected. Most recently, B. prokopi has been treated as a member of the infraclass Hydropalaeoptera, which also includes the Odonatoptera and Panephemeroptera. Bojophlebia is considered a sister group of all other members of the Hydropalaeoptera. A fossil that was described as a nymph of Bojophlebia is now considered to be a separate taxon, Carbotriplura kukalovae. The original description interpreted structures such as eyes and antennae, however these structures cannot be confirmed after restudy, although this may be an example of over-interpretation by Kukalová-Peck, as has happened with other extinct insects such as Carbotriplura and Gerarus.
Oligotypus is an extinct genus of griffinfly in the family Paralogidae. This genus is known from 4 species from the Carboniferous to Permian.
