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Plant fruit: the fleshy nutritious part of plants that animal dispense by eating independently came about in flowering plants and in some gymnosperms like: ginkgo and cycads. [239] Water transport systems, like vascular plant systems, with water conducting vessels, independently came about in horsetails, club mosses, ferns, and gymnosperms. [240]
Synapsids (precursors to mammals) separate from sauropsids (reptiles) in late Carboniferous. [88] 305 Ma The Carboniferous rainforest collapse occurs, causing a minor extinction event, as well as paving the way for amniotes to become dominant over amphibians and seed plants over ferns and lycophytes. First diapsid reptiles (e.g. Petrolacosaurus ...
Comparative study of the anatomy of groups of animals or plants reveals that certain structural features are basically similar. For example, the basic structure of all flowers consists of sepals , petals , stigma, style and ovary ; yet the size, colour , number of parts and specific structure are different for each individual species.
Comparative anatomy studies similarities and differences in organisms. The image shows homologous bones in the upper limb of various vertebrates. Comparative anatomy is the study of similarities and differences in the anatomy of different species. It is closely related to evolutionary biology and phylogeny [1] (the evolution of species).
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy.
Amphibians are ectothermic, anamniotic, four-limbed vertebrate animals that constitute the class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all tetrapods excluding the amniotes (tetrapods with an amniotic membrane , such as modern reptiles , birds and mammals ).
The oldest known animal that may have been an amniote, a reptile rather than an amphibian, is Casineria [3] [4] (though it has also been argued to be a temnospondyl amphibian). [5] A series of footprints from the fossil strata of Nova Scotia, dated to 315 million years, show typical reptilian toes and imprints of scales. [6]
Rhynia thus falls midway between mosses and early vascular plants like ferns and clubmosses. From a carpet of moss-like gametophytes, the larger Rhynia sporophytes grew much like simple clubmosses, spreading by means of horizontal growing stems growing rhizoids that anchored the plant to the substrate.