ammonit.ru Палеонтологическия, Paleontology
Логин
Пароль

Регистрация

Забыли пароль?

 | Палеонтология, палеонтологический портал "Аммонит.ру" |   English version of paleontological portal Ammonit.ru |  Места находок | Геохронологическая шкала | Типы окаменелостей |

 | Виртуальный палеонтологический музей | Публикации | Новости палеонтологии | Пользователи  | Палеонтологические тэги |  

Macroconchs

Macroconchs is a paleobiological term introduced by J.Callomon. This term denotes ammonites which reached maturity at a relatively large size. Macroconchs also have other distinctive features: a lack of adult aperture modifications on the final apertural edge (lappets, long ventral rostrum), simplification and often smoothing of sculpture on the terminal body chamber, changing of coiling angle on the last whorl. Most paleontologists believe that macroconchs are shells of female ammonites, whereas microconchs are male shells. The same type of sexual dimorphism is present in modern octopods which belong to Argonautidae family. The large size of female ammonite shells is likely related to the production of large numbers of eggs or even brooding eggs inside the body chamber (ovoviviparity). At the same time the smallest macroconchs are often smaller than the largest microconchs (probably due to the fact that the fast-growing cephalopods reach maturity at different sizes, depending on the ambient temperature).

The text was added by: Alex

Самые популярные фотографии, связанные с этим ключевым словом: / Most popular photos related with this paleontological keyword:

Жемчужина Широкого Буерака отвели душу Макроконх Cardioceras Kosmoceras (Sigaloceras) enodatum Parkinsonia бабушка аммонит крупняк. рогатый Peltoceras schroederi

Смотреть все фото по этому тэгу >>> // See all photos with this keyword >>>

С ключевым словом "Macroconchs" связаны:

Following items are related with the keyword
"Macroconchs":

153 фотографии

1 новость

4 публикации

Ключевые слова, связанные со словом "Macroconchs":
Keywords, related with "Macroconchs":

A: Ammonites

M: Megaconchs | Microconchs

А: аммониты

М: макроконхи | мегаконхи

Постоянный адрес тэга:
Permanent link:

HTML-ссылка на тэг:
HTML-link to this page: