Unlaid egg discovered in ancient bird fossil

first_img Click to view the privacy policy. Required fields are indicated by an asterisk (*) Barbara Marrs Sign up for our daily newsletter Get more great content like this delivered right to you! Country By John PickrellMar. 20, 2019 , 6:00 AM Unlaid egg discovered in ancient bird fossil Country * Afghanistan Aland Islands Albania Algeria Andorra Angola Anguilla Antarctica Antigua and Barbuda Argentina Armenia Aruba Australia Austria Azerbaijan Bahamas Bahrain Bangladesh Barbados Belarus Belgium Belize Benin Bermuda Bhutan Bolivia, Plurinational State of Bonaire, Sint Eustatius and Saba Bosnia and Herzegovina Botswana Bouvet Island Brazil British Indian Ocean Territory Brunei Darussalam Bulgaria Burkina Faso Burundi Cambodia Cameroon Canada Cape Verde Cayman Islands Central African Republic Chad Chile China Christmas Island Cocos (Keeling) Islands Colombia Comoros Congo Congo, the Democratic Republic of the Cook Islands Costa Rica Cote d’Ivoire Croatia Cuba Curaçao Cyprus Czech Republic Denmark Djibouti Dominica Dominican Republic Ecuador Egypt El Salvador Equatorial Guinea Eritrea Estonia Ethiopia Falkland Islands (Malvinas) Faroe Islands Fiji Finland France French Guiana French Polynesia French Southern Territories Gabon Gambia Georgia Germany Ghana Gibraltar Greece Greenland Grenada Guadeloupe Guatemala Guernsey Guinea Guinea-Bissau Guyana Haiti Heard Island and McDonald Islands Holy See (Vatican City State) Honduras Hungary Iceland India Indonesia Iran, Islamic Republic of Iraq Ireland Isle of Man Israel Italy Jamaica Japan Jersey Jordan Kazakhstan Kenya Kiribati Korea, Democratic People’s Republic of Korea, Republic of Kuwait Kyrgyzstan Lao People’s Democratic Republic Latvia Lebanon Lesotho Liberia Libyan Arab Jamahiriya Liechtenstein Lithuania Luxembourg Macao Macedonia, the former Yugoslav Republic of Madagascar Malawi Malaysia Maldives Mali Malta Martinique Mauritania Mauritius Mayotte Mexico Moldova, Republic of Monaco Mongolia Montenegro Montserrat Morocco Mozambique Myanmar Namibia Nauru Nepal Netherlands New Caledonia New Zealand Nicaragua Niger Nigeria Niue Norfolk Island Norway Oman Pakistan Palestine Panama Papua New Guinea Paraguay Peru Philippines Pitcairn Poland Portugal Qatar Reunion Romania Russian Federation Rwanda Saint Barthélemy Saint Helena, Ascension and Tristan da Cunha Saint Kitts and Nevis Saint Lucia Saint Martin (French part) Saint Pierre and Miquelon Saint Vincent and the Grenadines Samoa San Marino Sao Tome and Principe Saudi Arabia Senegal Serbia Seychelles Sierra Leone Singapore Sint Maarten (Dutch part) Slovakia Slovenia Solomon Islands Somalia South Africa South Georgia and the South Sandwich Islands South Sudan Spain Sri Lanka Sudan Suriname Svalbard and Jan Mayen Swaziland Sweden Switzerland Syrian Arab Republic Taiwan Tajikistan Tanzania, United Republic of Thailand Timor-Leste Togo Tokelau Tonga Trinidad and Tobago Tunisia Turkey Turkmenistan Turks and Caicos Islands Tuvalu Uganda Ukraine United Arab Emirates United Kingdom United States Uruguay Uzbekistan Vanuatu Venezuela, Bolivarian Republic of Vietnam Virgin Islands, British Wallis and Futuna Western Sahara Yemen Zambia Zimbabwe Email For the first time, researchers have found an unlaid egg inside a fossilized bird. The find—belonging to a sparrow-size flyer that lived in northwestern China 110 million years ago—is especially remarkable because fully formed eggs typically only stay within an adult bird for about 24 hours.Researchers were initially puzzled by the discovery, as they never suspected the unusual, squashed mass within the headless fossil’s abdomen (seen as a flattened brown layer in the center of the picture) could be an egg. But a microscopic analysis of a fragment revealed it to be eggshell. Further study suggested structural abnormalities that hint that the egg may have been the cause of this bird’s demise, the paleontologists report today in Nature Communications.The fossil eggshell’s structure doesn’t have the correct proportions seen in healthy eggs and consists of multiple layers of shell. This indicates a condition called “egg-binding,” where an egg becomes trapped inside a bird, the team argues. This can occur in chickens and small varieties of modern pet birds under stress and likely also led to the death of this long-lost, dinosaur-era relative. This makes the discovery “the oldest documented case of this common reproductive disorder,” the researchers say. Intriguingly, the eggshell features microscopic spheres of calcium phosphate, which is seen today in birds that nest in humid, infection-prone environments. This waterproofing suggests it was a species that nested near water and buried its eggs in the ground.The team has christened the bird Avimaia schweitzerae. (Avimaia means “mother bird”; and schweitzerae honors paleontologist Mary Schweitzer.)last_img read more