畅玩棋牌游戏下载

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                                1.  畅玩棋牌游戏下载 >> 科学传播 >> 科普动态

                                科普动态

                                【中新网】科学家最新研究:与恐龙食性差异或助鸟类躲过大灭绝

                                发表日期:2020-04-26来源:放大 缩小
                                植食性古鸟类(左)和小型掠食性恐龙(右)的生态复原场景。与肉食性恐龙同处在一个生态系统下的中生代鸟类,演化出不同的取食习性,例如以种子、果实为主的植食性和以小型昆虫为食的杂食性,避免了直接与肉食性恐龙的食物竞争。 郑秋旸/绘图 摄

                                  中国科学家最新研究:与恐龙食性差异或助鸟类躲过大灭绝 

                                  BEIJING4YUE25RIDIAN (JIZHE SUNZIFA)6500WANNIANQIANDEDAMIEJUESHIJIANZHONG,YUNSHIZHUANGJIDIQIUJIPINFANHUOSHANHUODONG,SHIDIQIUZHONGNIANBUJIANTIANRI,YILAIGUANGHEZUOYONGDEZHIWUDALIANGSIWANG,ZUIZHONGDAOZHIZHISHIXING、ROUSHIXINGKONGLONGDENGXIANGJIMIEJUE。

                                  ZAIZHEIYISHIWULIANBENGKUIYINFADEDAMIEJUESHIJIANZHONG,KONGLONGDEHOUDAINIAOLEIWEIHEDEYIXINGCUN?ZHEIYIXUEJIEZHANGQIGUANZHUDEGUSHENGWUYANHUAMITUAN,JINRIBEIZHONGGUOKEXUEJIADEZUIXINYANJIUCHENGGUOPOJIE——YUKONGLONGDESHIXINGCHAYI,KENENGSHINIAOLEIDUOGUODAMIEJUEERXINGCUNZHIJINDEGUANJIAN。

                                白垩纪早期古鸟类-会鸟的化石标本(黑色箭头标示牙齿位置),收藏于中科院古脊椎所。 李志恒/供图 摄

                                  JIZHE25RICONGZHONGGUOKEXUEYUANGUJIZHUIDONGWUYUGURENLEIYANJIUSUO(ZHONGKEYUANGUJIZHUISUO)HUOXI,GAISUOLIZHIHENGTUANDUIYUTAIWANTONGBUFUSHEYANJIUZHONGXINDENGDUOJIAHEZUODANWEI,GONGTONGDUIYUNIAOLEIQINYUANGUANXIZUIJIEJINDEFEINIAOLEIKONGLONGZHIGUNIAOLEIDEYACHIYANHUATEZHENGJINXINGTANTAO,YANJIUCHENGGUOJIESHI,NIAOLEIYUKONGLONGZHIJIANSHIXINGDECHAYIHENKENENGSHIQINENGGOUDUOGUO6500WANNIANQIANZAIBIANDEGUANJIAN。

                                畅玩棋牌游戏下载  ZHONGKEYUANGUJIZHUISUOJIESHAO,LIZHIHENGYANJIUTUANDUITONGGUOTONGBUFUSHEDEGAOJIEXICHUANTOUSHIX-GUANGXIANWEIJING,DUIXIAOXINGFEINIAOLEIKONGLONG——BAOHANSHANGCHILONG、JINNIAOLONG、XIAODAOLONG,YIJIGUNIAOLEI——BAOHANJINNIAOLEI、FANNIAOLEI、HUINIAO、REHENIAODENGYACHIDEWEIJIEGOUJINXINGDUIBIGUANCHAHEYANJIU,FAXIANJINGUANJIANDANDEYOUZHICENGZAIZAOQIGUNIAOLEIZHONGDOUYOUBAOLIU,DANYAYOUZHIYUYABENZHIZHIJIANDEDUOKONGZHAOYABENZHICENGJIEYIXIAOSHI,ERDUOKONGZHAOYABENZHICENGBEIRENWEISHIROUSHIXINGKONGLONGYACHIZHONGFAYUDE、BIMIANQIZAILVESHIGUOCHENGZHONGYACHIDUANLIEDETESHUBIZHENBAOHUJIEGOU。BUJINZAIGUNIAOLEIZHONG,CICIYANJIUDEYIZHONGXIAODAOLONGBIAOBENDEZHAOYABENZHICENGYEYIJINGXIAOSHI。

                                白垩纪古鸟类与小型非鸟兽脚类恐龙的牙齿内部微结构演化(a-伤齿龙,b-近鸟龙,c、d-小盗龙,e-反鸟未定种,f-今鸟类,g-长翼鸟,h-会鸟)。高解析同步辐射显微影像显示出牙齿中多孔罩牙本质(IGS)在古鸟类和一小盗龙中已消失,提供了食性转化的演化证据。 李志恒/供图 摄

                                畅玩棋牌游戏下载  YANJIUTUANDUIRENWEI,SHANGSHUFAXIANYIWEIZHENIAOLEIYUBUFENQINYUANGUANXIXIANGJINDEKONGLONG,QIYACHIBUZAIXUYAOTESHUDELIXUEBAOHUJIEGOU,ZHEIJIANJIEZHENGSHILEQIZAIYINSHIXIGUAN,RUYAOHELIYULVESHIXINGFANGMIAN,YUROUSHIXINGKONGLONGYICHANSHENGJIDACHAYI,TONGGUOSHIXINGZHUANHUANBIKAIYUROUSHIXINGKONGLONGDUISHIWUSHENGTAIWEIDEJINGZHENG,SHIYINGNENGLIJIDATIGAO,CONGERDUGUODAMIEJUESHIJIANDEZUIJIANNANSHIKE。

                                  YANJIUTUANDUIZHICHU,XIANGJIAOYUGUNIAOLEIDEPUBIANXINGZHISHIHUOZASHIHUADEYANJINQUSHI,SUIRANFEINIAOLEIKONGLONGDESHAOSHULEIQUN,RUXIAODAOLONGYEFASHENGLEQUTONGYANHUA,DANRENGNANYIBIMIANMIEJUEDEWEIJI。

                                  JULEJIE,ZHONGGUOKEXUEJIAWANCHENGDEZHEIXIANGKONGLONGXIANGNIAOLEIYANHUAZHONGYAOYANJIUCHENGGUOLUNWEN,YIHUOGUOJIXUESHUQIKAN《BMCJINHUASHENGWUXUE》(BMC Evolutionary Biology)ZAIXIANFABIAO。(WAN)

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