Editing Drosophila (section)

===Reproduction===
Males of this genus are known to have the longest [[spermatozoon|sperm cells]] of any studied organism on Earth, including one species, ''[[Drosophila bifurca]]'', that has sperm cells that are {{convert|58|mm|abbr=on}} long.<ref name="Pitnick">{{cite journal | vauthors = Pitnick S, Spicer GS, Markow TA | title = How long is a giant sperm? | journal = Nature | volume = 375 | issue = 6527 | pages = 109 | date = May 1995 | pmid = 7753164 | doi = 10.1038/375109a0 | s2cid = 4368953 | bibcode = 1995Natur.375Q.109P | doi-access = free | author-link3 = Therese Ann Markow }}</ref> The cells mostly consist of a long, thread-like tail, and are delivered to the females in tangled coils. The other members of the genus ''Drosophila'' also make relatively few giant sperm cells, with that of ''D. bifurca'' being the longest.<ref name="Joly-2007">{{cite journal | vauthors = Joly D, Luck N, Dejonghe B | title = Adaptation to long sperm in Drosophila: correlated development of the sperm roller and sperm packaging | journal = Journal of Experimental Zoology. Part B, Molecular and Developmental Evolution | volume = 310 | issue = 2 | pages = 167–178 | date = March 2008 | pmid = 17377954 | doi = 10.1002/jez.b.21167 | bibcode = 2008JEZB..310..167J }}</ref> ''D. melanogaster'' sperm cells are a more modest 1.8&nbsp;mm long, although this is still about 35 times longer than a human sperm. Several species in the ''D. melanogaster'' species group are known to mate by [[traumatic insemination]].<ref name="kamimura">{{cite journal | vauthors = Kamimura Y | title = Twin intromittent organs of Drosophila for traumatic insemination | journal = Biology Letters | volume = 3 | issue = 4 | pages = 401–404 | date = August 2007 | pmid = 17519186 | pmc = 2391172 | doi = 10.1098/rsbl.2007.0192 }}</ref>

''Drosophila'' species vary widely in their reproductive capacity. Those such as ''D. melanogaster'' that breed in large, relatively rare resources have [[ovaries]] that mature 10–20 eggs at a time, so that they can be laid together on one site. Others that breed in more-abundant but less nutritious substrates, such as leaves, may only lay one egg per day. The eggs have one or more respiratory filaments near the anterior end; the tips of these extend above the surface and allow oxygen to reach the embryo. Larvae feed not on the vegetable matter itself, but on the [[yeast]]s and [[microorganism]]s present on the decaying breeding substrate. Development time varies widely between species (between 7 and more than 60 days) and depends on the environmental factors such as [[temperature]], breeding substrate, and crowding.

Fruit flies lay eggs in response to environmental cycles. Eggs laid at a time (e.g., night) during which likelihood of survival is greater than in eggs laid at other times (e.g., day) yield more larvae than eggs that were laid at those times. ''Ceteris paribus'', the habit of laying eggs at this 'advantageous' time would yield more surviving offspring, and more grandchildren, than the habit of laying eggs during other times. This differential reproductive success would cause ''D. melanogaster'' to adapt to environmental cycles, because this behavior has a major reproductive advantage.<ref>{{cite journal | vauthors = Howlader G, Sharma VK | title = Circadian regulation of egg-laying behavior in fruit flies Drosophila melanogaster | journal = Journal of Insect Physiology | volume = 52 | issue = 8 | pages = 779–785 | date = August 2006 | pmid = 16781727 | doi = 10.1016/j.jinsphys.2006.05.001 | bibcode = 2006JInsP..52..779H }}</ref>

Their median lifespan is 35–45 days.<ref>{{cite journal | vauthors = Broughton SJ, Piper MD, Ikeya T, Bass TM, Jacobson J, Driege Y, Martinez P, Hafen E, Withers DJ, Leevers SJ, Partridge L | display-authors = 6 | title = Longer lifespan, altered metabolism, and stress resistance in Drosophila from ablation of cells making insulin-like ligands | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 102 | issue = 8 | pages = 3105–3110 | date = February 2005 | pmid = 15708981 | pmc = 549445 | doi = 10.1073/pnas.0405775102 | doi-access = free | bibcode = 2005PNAS..102.3105B }}</ref>

{{multiple image|total_width=600|align=center
| title = Lifecycle of ''Drosophila''
| width1=168|height1=140|image1 = Drosophila egg.png
| caption1 = Egg
| width2=598|height2=337|image2 = Fruit fly larva 01.jpg
| caption2 = Larva
| width3=688|height3=460|image3 = Fruit fly pupae 01.jpg
| caption3 = Pupae (brown specimens are older than the white ones)
| width4=546|height4=424|image4=Drosophila melanogaster - side (aka).jpg
| caption4=Adult ''D. melanogaster''
}}