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Embryonic development of a salamander, filmed in the 1920s. In temperate regions, reproduction is usually seasonal and salamanders may migrate to breeding grounds. Males usually arrive first and in some instances set up territories. Typically, a larval stage follows in which the organism is fully aquatic.
Adult lungless salamanders have four limbs, with four toes on the fore limbs, and usually with five on the hind limbs. Within many species, mating and reproduction occur solely on land. Accordingly, many species also lack an aquatic larval stage, a phenomenon known as direct development in which the offspring hatch as fully-formed, miniature ...
Newt. A newt is a salamander in the subfamily Pleurodelinae. The terrestrial juvenile phase is called an eft. Unlike other members of the family Salamandridae, newts are semiaquatic, alternating between aquatic and terrestrial habitats. Not all aquatic salamanders are considered newts, however.
Neurulation. Neurulation refers to the folding process in vertebrate embryos, which includes the transformation of the neural plate into the neural tube. [ 1] The embryo at this stage is termed the neurula . The process begins when the notochord induces the formation of the central nervous system (CNS) by signaling the ectoderm germ layer above ...
Animal embryonic development. Diagram of stages of embryo development to a larval and adult stage. In developmental biology, animal embryonic development, also known as animal embryogenesis, is the developmental stage of an animal embryo. Embryonic development starts with the fertilization of an egg cell (ovum) by a sperm cell, ( spermatozoon ...
The alpine salamander ( Salamandra atra) is a black salamander that can be found in the French Alps, and through the mountainous range in Europe. [2] It is a member of the genus Salamandra. Their species name, atra, may be derived from the Latin ater, meaning dull black. [3] The salamanders' coloration has evolved over time, as some species are ...
The spotted salamander or yellow-spotted salamander ( Ambystoma maculatum) is a mole salamander [ 2] common in eastern United States and Canada. [ 1] It is the state amphibian of Ohio and South Carolina. The species ranges from Nova Scotia, to Lake Superior, to southern Georgia and Texas. [ 3]
Deuterostomes (from Greek: lit. 'mouth second') are bilaterian animals of the superphylum Deuterostomia ( / ˌdjuːtərəˈstoʊmi.ə / ), [ 3][ 4] typically characterized by their anus forming before the mouth during embryonic development. Deuterostomia is further divided into 4 phyla: Chordata, Echinodermata, Hemichordata, and the extinct ...