Direct development is a concept in biology. It refers to forms of growth to adulthood that do not involve metamorphosis. An animal undergoes direct development if the immature organism resembles a small adult rather than having a distinct larval form.[1] A frog that hatches out of its egg as a small frog undergoes direct development. A frog that hatches out of its egg as a tadpole does not.
Direct development is the opposite of complete metamorphosis. An animal undergoes complete metamorphosis if it becomes a non-moving thing, for example a pupa in a cocoon, between its larval and adult stages.[2]
Examples
edit- Most frogs in the genus Callulina hatch out of their eggs as froglets.
- Springtails and mayflies, called ametabolous insects, undergo direct development.[3]
References
edit- ^ Fang Yan; Xiaolong Liu; Yinpeng Zhang; Zhiyong Yuan (May 28, 2021). "Direct development of the bush frog Raorchestes longchuanensis (Yang and Li 1978) under laborary conditions in Southern China". Journal of Natural History. 55 (1–2): 123–132. doi:10.1080/00222933.2021.1895349. S2CID 236202923. Retrieved March 7, 2023.
- ^ Jens Rolff; Paul R. Johnston; Stuart Reynolds (August 26, 2019). "Complete metamorphosis of insects". Philos Trans R Soc Lond B Biol Sci. 374 (1783). doi:10.1098/rstb.2019.0063. PMC 6711294. PMID 31438816.
- ^ Scott F. Gilbert (2000). "Metamorphosis: The Hormonal Reactivation of Development". Developmental Biology (6 ed.). Sunderland, MA: Sinauer Associates. Retrieved March 19, 2023.
