Editing Seed (section)

=== Dispersal ===
{{Main|Seed dispersal}}
Unlike animals, plants are limited in their ability to seek out favorable conditions for life and growth. As a result, plants have evolved many ways to [[Biological dispersal|disperse]] their offspring by dispersing their seeds (see also [[vegetative reproduction]]). A seed must somehow "arrive" at a location and be there at a time favorable for germination and growth. When the fruits open and release their seeds in a regular way, it is called [[dehiscence (botany)|dehiscent]], which is often distinctive for related groups of plants; these fruits include [[Capsule (fruit)|capsules]], [[Follicle (fruit)|follicles]], [[legume]]s, [[silicle]]s and [[silique]]s. When fruits do not open and release their seeds in a regular fashion, they are called indehiscent, which include the fruits [[achene]]s, [[Caryopsis|caryopses]], [[Nut (fruit)|nuts]], [[samara (fruit)|samaras]], and [[utricle (fruit)|utricles]].<ref>Jones, Samuel B., and Arlene E. Luchsinger. 1979. ''Plant systematics. McGraw-Hill series in organismic biology''. New York: McGraw-Hill. p. 195.</ref>

==== By wind (anemochory) ====
[[File:Taraxacum sect. Ruderalia MHNT.jpg|thumb|Dandelion seeds are contained within [[achene]]s, which can be carried long distances by the wind.]]
[[File:Milkweed-in-seed2.jpg|right|upright|thumb|The seed pod of [[milkweed]] (''Asclepias syriaca'')]]
* Some seeds (e.g., [[pine]]) have a wing that aids in wind dispersal.
* The dustlike seeds of [[orchid]]s are carried efficiently by the wind.
* Some seeds (e.g. [[milkweed]], [[Populus|poplar]]) have hairs that aid in wind dispersal.<ref name="california_desert_flowers_an_introduction_to_families_genera">{{cite book  | last1 = Morhardt | first1 = Sia | last2 = Morhardt | first2 = Emil | last3 = Emil Morhardt | first3 = J. | title = California desert flowers: an introduction to families, genera, and species | url = https://books.google.com/books?id=1XyN-u-Bk40C&pg=PA24| year = 2004 | publisher = University of California Press | location = Berkeley  | isbn = 978-0-520-24003-2 | page = 24 }}</ref>

Other seeds are enclosed in fruit structures that aid wind dispersal in similar ways:
* [[Dandelion]] achenes have hairs.
* [[Maple]] samaras have two wings.

==== By water (hydrochory) ====
* Some plants, such as ''[[Mucuna]]'' and ''[[Dioclea (plant)|Dioclea]]'', produce buoyant seeds termed sea-beans or drift seeds because they float in rivers to the oceans and wash up on beaches.<ref>{{cite web|url=http://www.seabean.com/|title=www.seabean.com – Sea-Beans and Drift Seeds|work=seabean.com|url-status=live|archive-url=https://web.archive.org/web/20060711180958/http://www.seabean.com/|archive-date=2006-07-11}}</ref>

==== By animals (zoochory) ====
* Seeds ([[burr (fruit)|burrs]]) with barbs or hooks (e.g. [[acaena]], [[burdock]], [[Rumex|dock]]) which attach to animal fur or feathers, and then drop off later.
* Seeds with a fleshy covering (e.g. [[apple]], [[cherry]], [[juniper]]) are eaten by animals ([[bird]]s, [[mammal]]s, [[reptile]]s, [[fish]]) which then disperse these seeds in their [[faeces|droppings]].
* Seeds ([[nut (fruit)|nuts]]) are attractive long-term storable food resources for animals (e.g. [[acorn]]s, [[hazel]]nut, [[walnut]]); the seeds are stored some distance from the parent plant, and some escape being eaten if the animal forgets them.

'''[[Myrmecochory]]''' is the dispersal of seeds by [[ant]]s. Foraging ants disperse seeds which have appendages called [[elaiosome]]s<ref>{{cite journal | author = Marinelli J | year = 1999 | title = Ants&nbsp;– The astonishing intimacy between ants & plants | url = http://www.bbg.org/gar2/topics/wildlife/1999sp_ants.html | journal = Plants & Gardens News | volume = 14 | issue = 1 | url-status=live | archive-url = https://web.archive.org/web/20060818062717/http://www.bbg.org/gar2/topics/wildlife/1999sp_ants.html | archive-date = 2006-08-18 }}</ref> (e.g. [[bloodroot]], [[trillium]]s, [[acacia]]s, and many species of [[Proteaceae]]). Elaiosomes are soft, fleshy structures that contain nutrients for animals that eat them. The ants carry such seeds back to their nest, where the elaiosomes are eaten. The remainder of the seed, which is hard and inedible to the ants, then germinates either within the nest or at a removal site where the seed has been discarded by the ants.<ref name="Ricklefs 1993">Ricklefs, Robert E. (1993) ''The Economy of Nature'', 3rd ed., p. 396. (New York: W.H. Freeman). {{ISBN|0-7167-2409-X}}.</ref> This dispersal relationship is an example of [[Mutualism (biology)|mutualism]], since the plants depend upon the ants to disperse seeds, while the ants depend upon the plants seeds for food. As a result, a drop in numbers of one partner can reduce success of the other. In [[South Africa]], the [[Argentine ant]] (''Linepithema humile'') has [[invasive species|invaded]] and displaced native species of ants. Unlike the native ant species, Argentine ants do not collect the seeds of ''[[Mimetes cucullatus]]'' or eat the elaiosomes. In areas where these ants have invaded, the numbers of ''Mimetes'' seedlings have dropped.<ref>{{cite journal | author = Bond, W.J. |author2=P. Slingsby  | year=1984 | title = Collapse of an ant-plant mutualism: The Argentine ant, ''Iridomyrmex humilis'' and myrmecochorous Proteaceae | journal = Ecology | volume=65 | issue = 4 | pages=1031–1037 | doi = 10.2307/1938311 | jstor = 1938311|bibcode=1984Ecol...65.1031B }}</ref>