Editing Frog (section)

====Eggs / frogspawn {{anchor|Frogspawn}}{{anchor|Frog spawn}}====
[[File:Frogspawn closeup.jpg|left|thumb|Frogspawn]]

Frogs may lay their eggs as clumps, surface films, strings, or individually. Around half of species deposit eggs in water, others lay eggs in vegetation, on the ground or in excavations.<ref>{{cite book|author=Mattison, Chris|year=2011|title=Frogs and Toads of the Worlds|publisher=Princeton University Press|page=91|isbn=978-0-691-14968-4}}</ref><ref>{{cite encyclopedia |url=https://www.britannica.com/animal/Anura/Natural-history#ref275977 |title=Anura: Egg laying and hatching|author1=Duellman, W. E. |author2=Zug, G. R. |encyclopedia=Encyclopædia Britannica |access-date=April 9, 2022}}</ref><ref>{{cite book |last1=Duellman|first1=William E.|last2=Trueb|first2=Linda|author-link2=Linda Trueb|last3=Arak|first3=Anthony|year=2002 |contribution=Frogs and toads |title=The Firefly Encyclopedia of Reptiles and Amphibians |editor=Halliday, Tim |editor2=Adler, Kraig |publisher=Firefly Books |page=67 |isbn=978-1-55297-613-5 }}</ref> The tiny [[Yellow-Striped Pygmy Eleuth|yellow-striped pygmy eleuth]] (''Eleutherodactylus limbatus'') lays eggs singly, burying them in moist soil.<ref>{{cite journal |author1=Estrada, Alberto R. |author2=Hedges, S. Blair |year=1996 |title=At the lower size limit in tetrapods: a new diminutive frog from Cuba (Leptodactylidae: Eleutherodactylus) |journal=Copeia |volume=1996 |issue=4 |pages=852–859 |jstor=1447647 |doi=10.2307/1447647 }}</ref> The [[Smoky Jungle Frog|smoky jungle frog]] (''Leptodactylus pentadactylus'') makes a nest of foam in a hollow. The eggs hatch when the nest is flooded, or the tadpoles may complete their development in the foam if flooding does not occur.<ref>{{cite web |url=http://amphibiaweb.org/cgi-bin/amphib_query?where-genus=Leptodactylus&where-species=pentadactylus |title=''Leptodactylus pentadactylus'' |author1=Whittaker, Kellie |author2=Chantasirivisal, Peera | date=December 2, 2005 |work=AmphibiaWeb |publisher=University of California, Berkeley |access-date=July 19, 2012}}</ref> The red-eyed treefrog (''Agalychnis callidryas'') deposits its eggs on a leaf above a pool and when they hatch, the larvae fall into the water below.<ref>{{cite web |url=http://amphibiaweb.org/cgi-bin/amphib_query?where-genus=Agalychnis&where-species=callidryas |title=''Agalychnis callidryas'' |date=June 27, 2007 |author=Whittaker, Kellie |work=AmphibiaWeb |publisher=University of California, Berkeley |access-date=July 19, 2012}}</ref>

In certain species, such as the [[wood frog]] (''Rana sylvatica''), [[Symbiosis|symbiotic]] unicellular green algae are present in the gelatinous material. It is thought that these may benefit the developing larvae by providing them with extra oxygen through [[photosynthesis]].<ref>{{cite journal |author=Gilbert, Perry W. |year=1942 |title=Observations on the eggs of ''Ambystoma maculatum'' with especial reference to the green algae found within the egg envelopes |journal=Ecology |volume=23 |issue=2 |pages=215–227  |jstor=1931088 |doi=10.2307/1931088|bibcode=1942Ecol...23..215G }}</ref> The interior of globular egg clusters of the [[Wood Frog|wood frog]] has also been found to be up to 6&nbsp;°C (11&nbsp;°F) warmer than the surrounding water and this speeds up the development of the larvae.<ref>{{cite journal |author1=Waldman, Bruce |author2=Ryan, Michael J. |year=1983 |title=Thermal advantages of communal egg mass deposition in wood frogs (''Rana sylvatica'') |journal=Journal of Herpetology |volume=17 |issue=1 |pages=70–72 |jstor=1563783 |doi=10.2307/1563783 }}</ref> The larvae developing in the eggs can detect vibrations caused by nearby predatory wasps or snakes, and will hatch early to avoid being eaten.<ref>{{cite journal| last=Warkentin| first=K.M.| year=1995| title=Adaptive plasticity in hatching age: a response to predation risk trade-offs| journal=Proceedings of the National Academy of Sciences| volume=92| pages=3507–3510| doi=10.1073/pnas.92.8.3507| pmid=11607529| issue=8| pmc=42196| bibcode=1995PNAS...92.3507W| doi-access=free}}</ref> In general, the length of the egg stage depends on the species and the environmental conditions. Aquatic eggs normally hatch within one week when the capsule splits as a result of [[enzyme]]s released by the developing larvae.<ref name=Stebbins2>{{cite book |title=A Natural History of Amphibians |last=Stebbins |first=Robert C. |author-link1=Robert C. Stebbins|author2=Cohen, Nathan W. |year=1995 |publisher=Princeton University Press |isbn=978-0-691-03281-8 |pages=179–194 }}</ref>

'''Direct development''', where eggs hatch into juveniles like small adults, is also known in many frogs, for example, ''[[Ischnocnema henselii]],''<ref>{{Cite journal|last1=Goldberg|first1=Javier|last2=Taucce|first2=Pedro P. G.|last3=Quinzio|first3=Silvia Inés|last4=Haddad|first4=Célio F. B.|last5=Vera Candioti|first5=Florencia|date=January 1, 2020|title=Increasing our knowledge on direct-developing frogs: The ontogeny of Ischnocnema henselii (Anura: Brachycephalidae)|url=http://www.sciencedirect.com/science/article/pii/S0044523119301196|journal=Zoologischer Anzeiger|language=en|volume=284|pages=78–87|doi=10.1016/j.jcz.2019.11.001|bibcode=2020ZooAn.284...78G |s2cid=209576535|issn=0044-5231}}</ref> ''[[Common coquí|Eleutherodactylus coqui]]'',<ref>{{Cite journal|last=Elinson|first=Richard P.|date=2001|title=Direct development: an alternative way to make a frog|url=https://onlinelibrary.wiley.com/doi/abs/10.1002/1526-968X%28200102%2929%3A2%3C91%3A%3AAID-GENE1009%3E3.0.CO%3B2-6|journal=Genesis|language=en|volume=29|issue=2|pages=91–95|doi=10.1002/1526-968X(200102)29:2<91::AID-GENE1009>3.0.CO;2-6|pmid=11170349|s2cid=32550621 |issn=1526-968X}}</ref> and ''[[Raorchestes ochlandrae]]'' and ''[[Raorchestes chalazodes]].''<ref>{{Cite journal|last=Seshadri|first=K.S.|date=2015|title=Rhacophorid Frogs Breeding in Bamboo: Discovery of a Novel Reproductive Mode from Western Ghats|url=https://www.researchgate.net/publication/287209620|journal=FrogLog|volume=23(4)|issue=116|pages=46–49}}</ref>