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О Филогенетическом Положении Однопроходных Млекопитающих (Mammalia, Monotremata) © 2014 Г

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О Филогенетическом Положении Однопроходных Млекопитающих (Mammalia, Monotremata) © 2014 Г ПАЛЕОНТОЛОГИЧЕСКИЙ ЖУРНАЛ, 2014, № 4, с. 83–104 УДК 569:551.6+7.575.8 О ФИЛОГЕНЕТИЧЕСКОМ ПОЛОЖЕНИИ ОДНОПРОХОДНЫХ МЛЕКОПИТАЮЩИХ (MAMMALIA, MONOTREMATA) © 2014 г. А. О. Аверьянов*, А. В. Лопатин** *Зоологический институт РАН, Санкт"Петербург *Санкт"Петербургский университет **Палеонтологический институт им. А.А. Борисяка РАН e"mail: [email protected], [email protected] Поступила в редакцию 12.03.2013 г. Принята к печати 04.09.2013 г. В качестве наиболее вероятной сестринской группы для однопроходных рассматриваются Henosfer ida из средней–поздней юры Западной Гондваны. Общим для обеих групп является продвинутое пре трибосфеническое строение нижних моляров при вероятном отсутствии протокона на верхних зубах и плезиоморфное сохранение постдентальных костей и “ложноуглового” отростка нижней челюсти. Общими для двух групп признаками также являются зубная формула с тремя молярами и положение меккелевой борозды, которая проходит вентральнее нижнечелюстного отверстия. В ходе дальнейшей эволюции у однопроходных сформировалось “маммальное” среднее ухо с тремя слуховыми косточка ми, как у териевых млекопитающих и мультитуберкулят. Вероятно, юрские лавразийские Shuotheri idae являются сестринской группой для гондванской клады Henosferida + Monotremata. У юрского шуотериида Pseudotribos наблюдается большое плезиоморфное сходство с однопроходными в стро ение грудного пояса (крупная межключица, неподвижно соединенная с ключицей). В линии, веду щей к териевым млекопитающим, и у мультитуберкулят, видимо, независимо происходили преоб разования плечевого пояса, связанные со становлением парасагиттальной постановки передних ко нечностей (редукция межключицы, ее подвижное сочленение с ключицей, редукция прокоракоида, развитие предостной ямки лопатки), и формирование “маммального” среднего уха с тремя слухо выми косточками. DOI: 10.7868/S0031031X14040059 “Корни монотремат нисходят к примитивным докодонтам или, скорее, к архаичным триконодонтам”. Л.П. Татаринов (2001) Находка в конце XVIII в. в Австралии, Тасма которой трактовалось бы в таких широких преде нии и на Новой Гвинее современных однопро лах, как для однопроходных: от сестринской ходных, или яйцекладущих, млекопитающих группы сумчатых (Gregory, 1947) до независимого (Monotremata) явилась одним из величайших происхождения от “эотерапсид” (Ивахненко, зоологических открытий. По многим особенно 2009) (см. также табл. 1). В данной работе прово стям физиологии, размножения и морфологии, дится анализ остеологических и миологических таким как откладка яиц, несовершенная терморе признаков монотремат, развитие которых можно гуляция, наличие клоаки, а также по строению проследить на ископаемом материале. хромосом, эти удивительные животные демон В статье приняты следующие сокращения: стрируют состояние, промежуточное между реп ЗИН – Зоологический институт РАН, СанктПе тилиями и териевыми млекопитающими (сумча тербург, Россия; AMNH – Американский музей тыми и плацентарными). С другой стороны, со естественной истории, НьюЙорк, США; IVPP – временный утконос и ехидны ведут крайне Институт палеонтологии и палеоантропологии, специализированный образ жизни (плавание и Пекин, Китай; NMV – Национальный музей питание донными беспозвоночными у первого и Виктории, Мельбурн, Австралия. рытье и питание почвенными беспозвоночными Мы благодарны Т. Ричу (Национальный музей у вторых). Такая специализация наложила глубо Виктории, Мельбурн, Австралия) за обсуждение кий отпечаток на строение однопроходных, делая проблемы происхождения монотремат, Э. Бух вычленение действительно плезиоморфных, уна гольц (Уэлсли колледж, Уэлсли, США) и А.Н. Куз следованных от предков признаков достаточно нецову (МГУ, Москва, Россия) – за консультации сложным. Пожалуй, не существует другой группы по поясничным позвонкам монотремат. Мы так млекопитающих, филогенетическое положение же благодарны А.Н. Кузнецову за рецензирова 83 6* 84 АВЕРЬЯНОВ, ЛОПАТИН Таблица 1. Филогенетические связи Monotremata по морфологическим данным (указаны преимущественно ра боты, основанные на кладистических принципах). Состав клады Monotremata варьирует у разных авторов, в наи более широком понимании в нее включаются вымершие таксоны Ausktribosphenida, Henosferida и Shuotheriidae Сестринская группа для Monotremata Ссылки Metatheria (Gregory, 1947; Kühne, 1973, 1977) Tribosphenida (Archer et al., 1985; KielanJaworowska et al., 1987) Multituberculata + Theria (Rowe, 1988) Theria (Wible, 1991; BinindaEmonds et al., 2007; Аверьянов, Лопатин, 2011) Cladotheria (KielanJaworowska, 1992; Rougier et al., 2007b; Gurovich, Beck, 2009) Политомия с Multituberculata и (Symmetrodonta, (Wible et al., 1995) Eutriconodonta, Cladotheria) Multituberculata, Eutriconodonta, (Rougier et al., 1996a; Rich et al., 2005a; Luo et al., 2007a; Trechnotheria Ji et al., 2009; Luo, 2011; Meng et al., 2011) Политомия с Multituberculata и Cladotheria (Fox, Meng, 1997) Multituberculata + Trechnotheria (Hu et al., 1997; Ji et al., 1999; Woodburne, 2003; Woodburne et al., 2003) Trechnotheria (Luo et al., 2001a; Rougier et al., 2011; O’Leary et al., 2013) Политомия с Multituberculata и Theria (Luo et al., 2001b) Multituberculata (Wang et al., 2001; Meng et al., 2003; Hu et al., 2005) (Eutriconodonta + (Multituberculata + Trechnotheria)) (Ji et al., 2002; Luo et al., 2002, 2007a, 2012; Rauhut et al., 2002; KielanJaworowska et al., 2004; Luo, Wible, 2005; Rowe et al., 2008; Yuan et al., 2013; Zheng et al., 2013; Zhou et al., 2013) Политомия с Eutriconodonta, Multituberculata (Ji et al., 2006) и Cladotheria Multituberculata, Symmetrodonta, Cladotheria (Li, Luo, 2006) Политомия с Morganucodonta, Docodonta (Meng et al., 2006) и (Eutriconodonta + (Multituberculata + Trechnotheria)) (Multituberculata + (Eutriconodonta + Trechnotheria)) (Luo et al., 2007b) Multituberculata + Cladotheria (Luo, 2011; Rowe et al., 2011) ние статьи и многочисленные замечания, способ са поможет решить сложный вопрос происхожде ствовавшие ее улучшению. Работа выполнена при ния монотремат (Thomas, 1890, с. 131). Однако поддержке гранта Президента РФ МД802.2009.4, морфология зубов утконоса оказалась довольно грантов РФФИ 070400393, 100401350, 1304 необычной и допускала различные интерпрета 01401 Программы Президиума РАН “Проблемы ции. Они считались похожими на зубы мультиту происхождения жизни и становления биосферы”. беркулят, ксенартр или десмостилий (Cope, 1888; Ameghino, 1908; Abel, 1926). ЗУБНАЯ СИСТЕМА Развитие зубов утконоса было впервые деталь но прослежено Дж. Вильсоном и Дж. Хиллом У плиоценовых и современных ехидн нет зу (Wilson, Hill, 1907). Они обнаружили закладки че бов. У взрослых утконосов вместо зубов исполь тырех заклыковых зубов в каждой челюсти, кото зуются роговые пластинки, и поэтому долгое вре рые обозначили как V, W, X, Y/w, x, y, z. Первому мя считалось, что у утконосов тоже нет зубов. На верхнему зубу и последнему нижнему нет анало стоящие зубы утконоса были обнаружены в конце гов в противоположной челюсти. Зубы V и w XIX в. (Poulton, 1888, 1889; Thomas, 1890; Stewart, представляют собой нефункциональные зубные 1892; Wilson, Hill, 1907). Это открытие породило закладки. Функционирующих зубов три в верх надежду, что изучение морфологии зубов утконо ней челюсти (W, X, Y) и три в нижней (x, y, z). Дан ПАЛЕОНТОЛОГИЧЕСКИЙ ЖУРНАЛ № 4 2014 О ФИЛОГЕНЕТИЧЕСКОМ ПОЛОЖЕНИИ ОДНОПРОХОДНЫХ МЛЕКОПИТАЮЩИХ 85 ные авторы предположили, что W/w являются по ских Henosferida (Martin, Rauhut, 2005; Rougier следними премолярами, а X, Y/x, y, z – молярами. et al., 2007b), Shuotheriidae (Luo et al., 2007b) и Эти зубы рассматривались как “квазипостоян претрибосфенических млекопитающих, в част ные” (у взрослых животных зубы замещены рого ности, у Peramus (McKenna, 1975; Prothero, 1981; вым клювом). Было обнаружено также по пять за Averianov et al., 2010a). У Multituberculata имелось чатков молочных зубов в каждой половине челю только по два моляра в каждой челюсти и послед сти, которые резорбировались на ранней стадии. ние премоляры обычно крупнее первых моляров, Согласно другой точке зрения, получившей боль что резко отличает их от монотремат. шое распространение, функциональные зубы ут Как отмечалось выше, функционирующие зу коноса являются молочными, а проблематичные бы были у олигоценмиоценовых утконосов рода зачатки относятся к “домолочной” генерации зу Obdurodon (Woodburne, Tedford, 1975; Archer et al., бов (Leche, 1910). 1992, 1993; Musser, Archer, 1998). Открытие ранне Следующая работа, посвященная развитию зу мелового монотремата Steropodon в Австралии бов утконоса, была выполнена Г. Грином (Green, (Archer et al., 1985) с зубами, сходными с таковы 1937), который установил формулу зачаточных ми Obdurodon, но более примитивного строения, зубов как I0, C1, P1–2, M1–3/i1–5, c1, p1–2, m1–3. позволило использовать признаки зубной систе Большая часть зубных зачатков резорбируется в мы монотремат для выяснения их филогенетиче эмбриогенезе и прорезается только по три корен ского положения. М. Арчер с коллегами (Archer ных зуба в верхней и нижней челюсти, которые et al., 1985) интерпретировали строение зубов сте примерно в месячном возрасте выпадают и заме роподона как трибосфеническое и связывали щаются роговыми пластинками. По Грину происхождение монотремат с древнейшими три (Green, 1937), функциональными зубами утконо босфеническими млекопитающими Aegialodon са являются P2, M1–2/m1–3. Такая формула при tidae. По мнению других авторов (KielanJa нимается в настоящее время (Woodburne, 2003). worowska et al., 1987), зубы стероподона нетрибо Согласно альтернативной интерпретации (West сфенические, и однопроходные происходят от ergaard,
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