909
次編輯
變更
稻大鼠
,無編輯摘要
==生理特徵==
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|<center><img src="https://gss3.bdstatic.com/7Po3dSag_xI4khGkpoWK1HF6hhy/baike/c0%3Dbaike80%2C5%2C5%2C80%2C26/sign=d49cfb5d8744ebf8797c6c6db890bc4f/fc1f4134970a304e9ae362a4d1c8a786c8175caf.jpg" width="250"></center><small>[[科罗拉多州]]的一般较为红色或黄褐色<br> [https://gss3.bdstatic.com/7Po3dSag_xI4khGkpoWK1HF6hhy/baike/c0%3Dbaike80%2C5%2C5%2C80%2C26/sign=d49cfb5d8744ebf8797c6c6db890bc4f/fc1f4134970a304e9ae362a4d1c8a786c8175caf.jpg 原圖鏈結] [https://baike.baidu.com/pic/%E7%A8%BB%E5%A4%A7%E9%BC%A0/4583054/0/c9bdddce7c010b6d93457ec8?fr=lemma&ct=single#aid=0&pic=c9bdddce7c010b6d93457ec8 圖片來自百度百科]</small>
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稻大鼠是中等身型的[[齧齒類]]，外觀像[[黑鼠]]及[[褐鼠]]，但上身及下身的顏色有所不同。<ref name=Wolfe1982>{{Cite journal en|author=Wolfe, J.L.|year=1982|url=http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/pdf/i0076-3519-176-01-0001.pdf|title=''Oryzomys palustris''|journal=Mammalian Species|volume=176|pages=1-5}}</ref>牠們的毛厚而且短。[[護毛]]很長，尖端呈銀色，稻大鼠的毛色會稍按地理性出現變化。當牠們游泳時，[[空氣]]會困在毛髮間，可以增加浮力及減少熱能流失。<ref name=Esher1978>{{Cite journal en|author=Esher, R.J., Wolfe, J.L. and Layne, J.N.|year=1978|url=http://www.jstor.org/stable/1380231|title=Swimming behavior of rice rats (''Oryzomys palustris'') and cotton rats (''Sigmodon hispidus'')|journal=Journal of Mammalogy|volume=59|issue=3|pages=551-8}}</ref>就像其他的[[稻鼠屬]]，雌鼠有8個[[額外乳房]]。
稻大鼠的[[胃部]]像[[棉鼠類]]的沒有分開兩個部份，前部有[[腺上皮]]覆蓋。<ref name=Weksler2006/>牠們沒有[[膽囊]]，屬於[[稻鼠族]]的[[共有衍徵]]。<ref name=Weksler2006/>[[染色體組型圖]]包含了56個[[染色體]]，染色體短臂基數為60（2n=56；FN=60）。從[[性染色體]]可以分辨稻大鼠與[[庫氏稻鼠]]，但很難單以此來分辨其他[[稻鼠屬]]的[[物種]]。<ref name=Hershkovitz1987>{{Cite journal en|author=Hershkovitz, P.M.|year=1987|url=http://www.jstor.org/stable/1381063|title=First South American record of Coues' marsh rice rat, ''Oryzomys couesi''|journal=Journal of Mammalogy|volume=68|issue=1|pages=152–4}}</ref>雖然稻大鼠沒有LINE-1[[反轉錄轉座子]]，但也會出現[[X染色體去活化]]。在[[實驗室]]中也有出現融合或有額外[[臼齒]]及毛色較淺的[[突變]]體。<ref name=Wolfe1982/>不正常臼齒似乎是由源自自體隱性的突變。<ref name=SofaerShaw1971>{{Cite journal en|author=Sofaer, J.A. and Shaw, J.H.|year=1971|url=http://dev.biologists.org/content/26/1/99.full.pdf|title=The genetics and development of fused and supernumerary molars in the rice rat|journal=Journal of Embryology and Experimental Morphology|volume=26|issue=1|pages=99–109}}</ref>稻大鼠的[[血細胞壓積]]約有50%<ref name=StallingHaynes1982>{{Cite journal en|author=Dick T Stalling and Howard Haines|year=1982|title=Effect of dehydration on water-turnover rates and hematocrits in the rice rat, ''oryzomys palustris''|journal=Comparative Biochemistry and Physiology Part A: Physiology|volume=72|issue=2|pages=301-6|doi=10.1016/0300-9629(82)90223-7}}</ref>，在[[齧齒類]]中算是高的；這可能是稻大鼠在水下游泳是增加氧容量的一種適應性。<ref name=StallingHaynes1982/>
===雄性生殖構造===
==行為及生態==
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|<center><img src="http://www.naturephoto-cz.com/photos/birds/%E4%BB%93%E9%B8%AE-147328.jpg" width="250"></center><small>[[倉鴞]]是稻大鼠的[[掠食者]]<br> [http://www.naturephoto-cz.com/photos/birds/%E4%BB%93%E9%B8%AE-147328.jpg 原圖鏈結] [https://www.google.com/search?q=%E5%80%89%E9%B6%9A&safe=active&sxsrf=ACYBGNTLJrxvzNxodrCrh7jmYYFDbs_3Kg:1579076044022&tbm=isch&source=iu&ictx=1&fir=jifHnR6KMllkaM%253A%252C8ZQuDcmITjlZKM%252C%252Fm%252F01kf0_&vet=1&usg=AI4_-kSbcN5ieaJ1SSQbez_xIUrn792SoQ&sa=X&ved=2ahUKEwjxk7XVlIXnAhWM7GEKHe4pAxMQ_B0wGnoECAoQAw#imgrc=jifHnR6KMllkaM: 圖片來自naturephoto]</small>
2009年[[IUCN紅色名錄]]將稻大鼠列為[[無危]]，原因是牠們普遍、廣泛分佈及數量穩定。在[[佛羅里達礁島群]]的稻大鼠較為稀有，數量更在下降，原因受到與[[黑鼠]]競爭、被[[家貓]]掠食、失去棲息地及失去遺傳變異的威脅，現正被認為是[[瀕危]]。<ref name=Wang2005/>
==參考資料=={{reflist|2}}
[[Category:380 動物學總論| ]]