PhylumIn biology, a phylum (ˈfaɪləm; : phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclature for algae, fungi, and plants accepts the terms as equivalent. Depending on definitions, the animal kingdom Animalia contains about 31 phyla, the plant kingdom Plantae contains about 14 phyla, and the fungus kingdom Fungi contains about 8 phyla.
PaleoceneThe Paleocene, (ˈpæli.əsiːn,_-i.oʊ-,_ˈpeɪli- ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek παλαιός palaiós meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history.
CycadCycads 'saIkaedz are seed plants that typically have a stout and woody (ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male or female. Cycads vary in size from having trunks only a few centimeters to several meters tall. They typically grow very slowly and live very long. Because of their superficial resemblance, they are sometimes mistaken for palms or ferns, but they are not closely related to either group.
Ginkgo bilobaGinkgo biloba, commonly known as ginkgo or gingko (ˈɡɪŋkoʊ,_ˈɡɪŋkɡoʊ ), also known as the maidenhair tree, is a species of gymnosperm tree native to China. It is the last living species in the order Ginkgoales, which first appeared over 290 million years ago. Fossils very similar to the living species, belonging to the genus Ginkgo, extend back to the Middle Jurassic epoch approximately 170 million years ago. The tree was cultivated early in human history and remains commonly planted.
AntarcticaAntarctica (ænˈtɑːrktᵻkə) is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation.
GymnospermThe gymnosperms (dZIm'noUsp@rmz lit. revealed seeds) are a group of seed-producing plants that includes conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae. The term gymnosperm comes from the composite word in γυμνόσπερμος (γυμνός and σπέρμα), literally meaning 'naked seeds'. The name is based on the unenclosed condition of their seeds (called ovules in their unfertilized state). The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants (angiosperms), which are enclosed within an ovary.
PaleobotanyPaleobotany, also spelled as palaeobotany, is the branch of botany dealing with the recovery and identification of plant remains from geological contexts, and their use for the biological reconstruction of past environments (paleogeography), and the evolutionary history of plants, with a bearing upon the evolution of life in general. A synonym is paleophytology. It is a component of paleontology and paleobiology. The prefix palaeo- or paleo- means "ancient, old", and is derived from the Greek adjective παλαιός, .
GnetophytaGnetophyta (nɛˈtɒfᵻtə,_ˈnɛtoʊfaɪtə) is a division of plants (alternatively considered the subclass Gnetidae or order Gnetales), grouped within the gymnosperms (which also includes conifers, cycads, and ginkgos), that consists of some 70 species across the three relict genera: Gnetum (family Gnetaceae), Welwitschia (family Welwitschiaceae), and Ephedra (family Ephedraceae). Fossilized pollen attributed to a close relative of Ephedra has been dated as far back as the Early Cretaceous.
ConiferConifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (pɪˈnɒfᵻtə,ˈpaɪnoʊfaɪtə), also known as Coniferophyta (ˌkɒnᵻfəˈrɒfᵻtə,-oʊfaɪtə) or Coniferae. The division contains a single extant class, Pinopsida. All extant conifers are perennial woody plants with secondary growth. The great majority are trees, though a few are shrubs. Examples include cedars, Douglas-firs, cypresses, firs, junipers, kauri, larches, pines, hemlocks, redwoods, spruces, and yews.
TreeIn botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees. Trees are not a monophyletic taxonomic group but consist of a wide variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight.