Origin of Birds: The Final Solution?1

نویسندگان

چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Molecular evidence for the origin of birds.

The major groups of amniote vertebrates appeared during a relatively short time span at the end of the Paleozoic Era, a fact that has caused difficulty in estimating their relationships. The fossil record suggests that crocodilians are the closest living relatives of birds. However, morphological characters and molecular sequence data from living amniotes have repeatedly challenged this hypothe...

متن کامل

The Origin and Diversification of Birds

Birds are one of the most recognizable and diverse groups of modern vertebrates. Over the past two decades, a wealth of new fossil discoveries and phylogenetic and macroevolutionary studies has transformed our understanding of how birds originated and became so successful. Birds evolved from theropod dinosaurs during the Jurassic (around 165-150 million years ago) and their classic small, light...

متن کامل

Fever of Unknown Origin with Final Diagnosis of Imported Malaria: A Case Study

One of the most important infectious diseases in the world is Malaria. About half of the world populations are exposed to the risk of the disease. The program for controlling and eradication of Malaria has been being conducted in our country since many years ago. One of the public health problems in the endemic and non-endemic countries is Imported Malaria which can ...

متن کامل

High Rates of Evolution Preceded the Origin of Birds

The origin of birds (Aves) is one of the great evolutionary transitions. Fossils show that many unique morphological features of modern birds, such as feathers, reduction in body size, and the semilunate carpal, long preceded the origin of clade Aves, but some may be unique to Aves, such as relative elongation of the forelimb. We study the evolution of body size and forelimb length across the p...

متن کامل

Origin of the irideal striated muscle in birds.

The aim of the present study was to elucidate the origin of the striated muscle cells in the avian iris. For this purpose we adopted interspecific transplantation between quail and chick embryos because quail cells can be used as biological markers in this system. We transplanted isotopically and isochronically (6- to 7-somite stage) a fragment of a dorsal part of the quail neural anlage into a...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: American Zoologist

سال: 2000

ISSN: 0003-1569

DOI: 10.1668/0003-1569(2000)040[0504:oobtfs]2.0.co;2