Clades in the context of Taxonomy

Slime molds or slime moulds are a variety of small or microscopic organisms in different groups. They have both single-celled and multicellular forms during their life cycle, the individual cells coming together to form fruiting bodies that produce spores. Most live in damp places such as rotting wood.

More formally, the slime molds are a polyphyletic assemblage of distantly related eukaryotic organisms in the Stramenopiles, Rhizaria, Discoba, Amoebozoa and Holomycota clades. Most are near-microscopic; those in the Myxogastria form larger plasmodial slime molds visible to the naked eye. Spores are often produced in macroscopic multicellular or multinucleate fruiting bodies formed through aggregation or fusion; aggregation is driven by chemical signals called acrasins. Slime molds contribute to the decomposition of dead vegetation; some are parasitic.

In biology, a phylum (/ˈfaɪləm/; pl.: phyla) is a level of classification, or taxonomic rank, that is 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 eight phyla. Current research in phylogenetics is uncovering the relationships among phyla within larger clades like Ecdysozoa and Embryophyta.

The name Apterygota is sometimes applied to a former subclass of small, agile insects, distinguished from other insects by their lack of wings in the present and in their evolutionary history; notable examples are the silverfish, the firebrat, and the jumping bristletails. Their first known occurrence in the fossil record is during the Devonian period, 417–354 million years ago. The group Apterygota is not a clade; it is paraphyletic, and not recognized in modern classification schemes. As defined, the group contains two separate clades of wingless insects: Archaeognatha comprises jumping bristletails, while Zygentoma comprises silverfish and firebrats. The Zygentoma are in the clade Dicondylia with winged insects, a clade that includes all other insects, while Archaeognatha is sister to this lineage.

The nymphs (younger stages) go through little or even no metamorphosis, hence they resemble the adult specimens (ametabolism).Currently, no species are listed as being at conservation risk.

Galanthus (from Ancient Greek γάλα, (gála, "milk") + ἄνθος (ánthos, "flower")), or snowdrop, is a small genus of approximately 20 species of bulbous perennial herbaceous plants in the family Amaryllidaceae. The plants have two linear leaves and a single small white drooping bell-shaped flower with six petal-like (petaloid) tepals in two circles (whorls). The smaller inner petals have green markings.

Snowdrops have been known since the earliest times under various names, but were named Galanthus in 1753. As the number of recognised species increased, various attempts were made to divide the species into subgroups, usually on the basis of the pattern of the emerging leaves (vernation). In the era of molecular phylogenetics this characteristic has been shown to be unreliable and now seven molecularly defined clades are recognised that correspond to the biogeographical distribution of species. New species continue to be discovered.

Diversification rates are the rates at which new species form (the Speciation rate, λ) and living species go extinct (the extinction rate, μ). Diversification rates can be estimated from fossils, data on the species diversity of clades and their ages, or phylogenetic trees. Diversification rates are typically reported on a per-lineage basis (e.g. speciation rate per lineage per unit of time), and refer to the diversification dynamics expected under a birth–death process.

A broad range of studies have demonstrated that diversification rates can vary tremendously both through time and across the tree of life. Current research efforts are focused on predicting diversification rates based on aspects of species or their environment. Diversification rates are also subject to various survivorship biases such as the "Push of the past"

A protein family is a group of evolutionarily related proteins. In many cases, a protein family has a corresponding gene family, in which each gene encodes a corresponding protein with a 1:1 relationship. The term "protein family" should not be confused with family as it is used in taxonomy.

Proteins in a family descend from a common ancestor and typically have similar three-dimensional structures, functions, and significant sequence similarity. Sequence similarity (usually amino-acid sequence) is one of the most common indicators of homology, or common evolutionary ancestry. Some frameworks for evaluating the significance of similarity between sequences use sequence alignment methods. Proteins that do not share a common ancestor are unlikely to show statistically significant sequence similarity, making sequence alignment a powerful tool for identifying the members of protein families. Families are sometimes grouped together into larger clades called superfamilies based on structural similarity, even if there is no identifiable sequence homology.