Connect with us

Science

An exquisitely preserved egg reveals what birds have inherited from dinosaurs

Published

on

An artist reconstruction of a baby oviraptorid in its egg. (Julius Csotonyi), Author provided

Oviraptorosaurs are a group of birdlike dinosaurs that were part of the ancestral dinosaur lineage that later gave rise to birds. Oviraptorosaurs walked on two legs, had a powerful toothless beak and were covered in feathers.

One of the first known species, Oviraptor philoceratops, was discovered in the 1920s when a skeleton was uncovered alongside a nest of eggs in Cretaceous rocks of Mongolia’s Gobi Desert. Paleontologists at the time assumed that the animal had died while attempting to raid the nest of another dinosaur — the name means “egg thief.”

It wasn’t until the mid-1990s, thanks to another discovery, that it was realized that the Oviraptor had actually been preserved in the act of tending to its own eggs. Since then, several important discoveries of oviraptorosaur eggs and nests have helped paleontologists reconstruct the reproductive and nesting habits of these unusual and birdlike dinosaurs.

In 2021, the latest such discovery revealed an exquisitely preserved skeleton of an oviraptorosaur curled in its egg. Our group of scientists from Canada, China and the United Kingdom led the study of this 70 million-year-old fossil from China, known as Baby Yingliang.

Baby Yingliang

Baby Yingliang is the first skeleton of a baby dinosaur showing precisely how the embryo was curled in its egg. Although the remains of other embryos have been found inside eggs before, their embryonic positions were uncertain because these skeletons were disarticulated or missing many bones.

During our study of the oviraptorosaur fossil, we recognized a trait that was long considered unique to birds that relates to how the embryo is tucked in the egg before hatching. In Baby Yingliang, the back is hunched in the blunt end of the egg and its head is lying on the abdomen with the tail curled along the opposite pointed end. The legs and feet are so folded up that they are lying on either side of the head and upper body. The embryo is positioned much like a chick that is only a few days from hatching.

Bird embryos, however, are known to tuck even further than what we found in Baby Yingliang. Immediately before hatching, the head moves under the wing where it rests on the shoulder, a position that helps ensure successful pipping and escape from the egg. Perhaps Baby Yingliang would have fully tucked like a bird if it had lived a little bit longer — its overall pose still suggests that such embryonic postures first evolved in dinosaurs before being passed down to birds.

colour illustration of dinosaur embryo curled up in its egg
An artist reconstruction of Baby Yingliang. (Lida Xing/Shoulin Animation), Author provided

Brooding behaviours

There are also other egg-related features that birds have inherited from dinosaurs like oviraptorosaurs. These include the architecture of eggshell layers, the shape of the egg (one end is more pointed), the pigments that cause egg colour and an open nest style. Even a nesting behaviour called brooding where the parent sits on top of the eggs, long-thought to be practised only by birds, first evolved in these dinosaurs.

In a stunning fossil discovery about 25 years ago, and a few like it since, the skeleton of an oviraptorosaur parent was found crouched on top of its eggs in a bird-like fashion.

What’s interesting is that oviraptorosaurs arranged their eggs in the nest in a unique manner noticeably different from birds. The eggs, often with over 30 in a nest, were arranged in two or three stacked rings, and were oriented like the spokes of a bike tire. If these dinosaurs used body heat to incubate their eggs like today’s brooding birds, the particular layout may have been crucial to expose all eggs to the parent’s body in the central space of the ring.

The few brooding oviraptorosaur fossils that have been discovered so far are all from smaller species at around 100 kilograms or less, no bigger than the size of an ostrich. The species to which Baby Yingliang belonged would also have been about this size — the 17 centimetre egg weighed half a kilogram in life and was from an egg cluster just over half a metre across. Giant oviraptorosaurs, which are quite rare, were considerably larger, as were their eggs and nests.

photograph of a fossilized circle of eggs
A fossilized giant oviraptorosaur nest from China. (Kohei Tanaka), Author provided

Giant eggs, giant nest

In 2017, I was part of a team that studied another embryonic skeleton, known as Baby Louie. The skeleton was found with a group of eggs belonging to a new species of giant oviraptorosaur, which we named Beibeilong. As the largest known dinosaur eggs, they were over 45 centimetres long and weighed more than five kilograms each. Based on their size, the female would have weighed over 1,100 kilograms and the nest diameter was some two metres across.

Assuming Beibeilong behaved like other oviraptorosaur species, an obvious question was: How did this behemoth sit on the nest without crushing the eggs?

In 2018, with another research team, we examined the eggs and nests of oviraptorosaur species ranging from 50 kilograms to the size of Beibeilong. We found that the eggshell of the Beibeilong-sized eggs was, at two millimetres thick, likely not strong enough to withstand the animal’s entire weight.

Interestingly, we noticed that while nearly all oviraptorosaur species laid a ring of eggs with an open central space, the size of that space was relatively larger in giant species like Beibeilong. This suggested that giant species were constructing their egg ring differently from smaller species so there was plenty of space in the centre to take the brunt of the body weight, also likely reducing their contact with the eggs.

Of birds and dinosaurs

Birds acquired many of their seemingly unique features from dinosaurs. Recent discoveries of fossilized eggs and nests have revealed birdlike characteristics in oviraptorosaurs associated with reproduction.

Several features related to their eggs, including brooding behaviours, are now known to have been passed down from dinosaurs, like oviraptorosaurs, to birds. The latest discovery, Baby Yingliang, uniquely preserves the embryonic position inside its egg, one that is remarkably similar to that of a bird embryo close to hatching.

Darla K. Zelenitsky, Associate Professor, Dinosaur paleobiology, University of Calgary

This article is republished from The Conversation under a Creative Commons license. Read the original article.

xosotin chelseathông tin chuyển nhượngcâu lạc bộ bóng đá arsenalbóng đá atalantabundesligacầu thủ haalandUEFAevertonxosofutebol ao vivofutemaxmulticanaisonbethttps://bsport.fithttps://onbet88.ooohttps://i9bet.bizhttps://hi88.ooohttps://okvip.athttps://f8bet.athttps://fb88.cashhttps://vn88.cashhttps://shbet.atbóng đá world cupbóng đá inter milantin juventusbenzemala ligaclb leicester cityMUman citymessi lionelsalahnapolineymarpsgronaldoserie atottenhamvalenciaAS ROMALeverkusenac milanmbappenapolinewcastleaston villaliverpoolfa cupreal madridpremier leagueAjaxbao bong da247EPLbarcelonabournemouthaff cupasean footballbên lề sân cỏbáo bóng đá mớibóng đá cúp thế giớitin bóng đá ViệtUEFAbáo bóng đá việt namHuyền thoại bóng đágiải ngoại hạng anhSeagametap chi bong da the gioitin bong da lutrận đấu hôm nayviệt nam bóng đátin nong bong daBóng đá nữthể thao 7m24h bóng đábóng đá hôm naythe thao ngoai hang anhtin nhanh bóng đáphòng thay đồ bóng đábóng đá phủikèo nhà cái onbetbóng đá lu 2thông tin phòng thay đồthe thao vuaapp đánh lô đềdudoanxosoxổ số giải đặc biệthôm nay xổ sốkèo đẹp hôm nayketquaxosokq xskqxsmnsoi cầu ba miềnsoi cau thong kesxkt hôm naythế giới xổ sốxổ số 24hxo.soxoso3mienxo so ba mienxoso dac bietxosodientoanxổ số dự đoánvé số chiều xổxoso ket quaxosokienthietxoso kq hôm nayxoso ktxổ số megaxổ số mới nhất hôm nayxoso truc tiepxoso ViệtSX3MIENxs dự đoánxs mien bac hom nayxs miên namxsmientrungxsmn thu 7con số may mắn hôm nayKQXS 3 miền Bắc Trung Nam Nhanhdự đoán xổ số 3 miềndò vé sốdu doan xo so hom nayket qua xo xoket qua xo so.vntrúng thưởng xo sokq xoso trực tiếpket qua xskqxs 247số miền nams0x0 mienbacxosobamien hôm naysố đẹp hôm naysố đẹp trực tuyếnnuôi số đẹpxo so hom quaxoso ketquaxstruc tiep hom nayxổ số kiến thiết trực tiếpxổ số kq hôm nayso xo kq trực tuyenkết quả xổ số miền bắc trực tiếpxo so miền namxổ số miền nam trực tiếptrực tiếp xổ số hôm nayket wa xsKQ XOSOxoso onlinexo so truc tiep hom nayxsttso mien bac trong ngàyKQXS3Msố so mien bacdu doan xo so onlinedu doan cau loxổ số kenokqxs vnKQXOSOKQXS hôm naytrực tiếp kết quả xổ số ba miềncap lo dep nhat hom naysoi cầu chuẩn hôm nayso ket qua xo soXem kết quả xổ số nhanh nhấtSX3MIENXSMB chủ nhậtKQXSMNkết quả mở giải trực tuyếnGiờ vàng chốt số OnlineĐánh Đề Con Gìdò số miền namdò vé số hôm nayso mo so debach thủ lô đẹp nhất hôm naycầu đề hôm naykết quả xổ số kiến thiết toàn quốccau dep 88xsmb rong bach kimket qua xs 2023dự đoán xổ số hàng ngàyBạch thủ đề miền BắcSoi Cầu MB thần tàisoi cau vip 247soi cầu tốtsoi cầu miễn phísoi cau mb vipxsmb hom nayxs vietlottxsmn hôm naycầu lô đẹpthống kê lô kép xổ số miền Bắcquay thử xsmnxổ số thần tàiQuay thử XSMTxổ số chiều nayxo so mien nam hom nayweb đánh lô đề trực tuyến uy tínKQXS hôm nayxsmb ngày hôm nayXSMT chủ nhậtxổ số Power 6/55KQXS A trúng roycao thủ chốt sốbảng xổ số đặc biệtsoi cầu 247 vipsoi cầu wap 666Soi cầu miễn phí 888 VIPSoi Cau Chuan MBđộc thủ desố miền bắcthần tài cho sốKết quả xổ số thần tàiXem trực tiếp xổ sốXIN SỐ THẦN TÀI THỔ ĐỊACầu lô số đẹplô đẹp vip 24hsoi cầu miễn phí 888xổ số kiến thiết chiều nayXSMN thứ 7 hàng tuầnKết quả Xổ số Hồ Chí Minhnhà cái xổ số Việt NamXổ Số Đại PhátXổ số mới nhất Hôm Nayso xo mb hom nayxxmb88quay thu mbXo so Minh ChinhXS Minh Ngọc trực tiếp hôm nayXSMN 88XSTDxs than taixổ số UY TIN NHẤTxs vietlott 88SOI CẦU SIÊU CHUẨNSoiCauVietlô đẹp hôm nay vipket qua so xo hom naykqxsmb 30 ngàydự đoán xổ số 3 miềnSoi cầu 3 càng chuẩn xácbạch thủ lônuoi lo chuanbắt lô chuẩn theo ngàykq xo-solô 3 càngnuôi lô đề siêu vipcầu Lô Xiên XSMBđề về bao nhiêuSoi cầu x3xổ số kiến thiết ngày hôm nayquay thử xsmttruc tiep kết quả sxmntrực tiếp miền bắckết quả xổ số chấm vnbảng xs đặc biệt năm 2023soi cau xsmbxổ số hà nội hôm naysxmtxsmt hôm nayxs truc tiep mbketqua xo so onlinekqxs onlinexo số hôm nayXS3MTin xs hôm nayxsmn thu2XSMN hom nayxổ số miền bắc trực tiếp hôm naySO XOxsmbsxmn hôm nay188betlink188 xo sosoi cầu vip 88lô tô việtsoi lô việtXS247xs ba miềnchốt lô đẹp nhất hôm naychốt số xsmbCHƠI LÔ TÔsoi cau mn hom naychốt lô chuẩndu doan sxmtdự đoán xổ số onlinerồng bạch kim chốt 3 càng miễn phí hôm naythống kê lô gan miền bắcdàn đề lôCầu Kèo Đặc Biệtchốt cầu may mắnkết quả xổ số miền bắc hômSoi cầu vàng 777thẻ bài onlinedu doan mn 888soi cầu miền nam vipsoi cầu mt vipdàn de hôm nay7 cao thủ chốt sốsoi cau mien phi 7777 cao thủ chốt số nức tiếng3 càng miền bắcrồng bạch kim 777dàn de bất bạion newsddxsmn188betw88w88789bettf88sin88suvipsunwintf88five8812betsv88vn88Top 10 nhà cái uy tínsky88iwinlucky88nhacaisin88oxbetm88vn88w88789betiwinf8betrio66rio66lucky88oxbetvn88188bet789betMay-88five88one88sin88bk88xbetoxbetMU88188BETSV88RIO66ONBET88188betM88M88SV88Jun-68Jun-88one88iwinv9betw388OXBETw388w388onbetonbetonbetonbet88onbet88onbet88onbet88onbetonbetonbetonbetqh88mu88Nhà cái uy tínpog79vp777vp777vipbetvipbetuk88uk88typhu88typhu88tk88tk88sm66sm66me88me888live8live8livesm66me88win798livesm66me88win79pog79pog79vp777vp777uk88uk88tk88tk88luck8luck8kingbet86kingbet86k188k188hr99hr99123b8xbetvnvipbetsv66zbettaisunwin-vntyphu88vn138vwinvwinvi68ee881xbetrio66zbetvn138i9betvipfi88clubcf68onbet88ee88typhu88onbetonbetkhuyenmai12bet-moblie12betmoblietaimienphi247vi68clupcf68clupvipbeti9betqh88onb123onbefsoi cầunổ hũbắn cáđá gàđá gàgame bàicasinosoi cầuxóc đĩagame bàigiải mã giấc mơbầu cuaslot gamecasinonổ hủdàn đềBắn cácasinodàn đềnổ hũtài xỉuslot gamecasinobắn cáđá gàgame bàithể thaogame bàisoi cầukqsssoi cầucờ tướngbắn cágame bàixóc đĩaAG百家乐AG百家乐AG真人AG真人爱游戏华体会华体会im体育kok体育开云体育开云体育开云体育乐鱼体育乐鱼体育欧宝体育ob体育亚博体育亚博体育亚博体育亚博体育亚博体育亚博体育开云体育开云体育棋牌棋牌沙巴体育买球平台新葡京娱乐开云体育mu88qh88
Continue Reading
Click to comment

Leave a Reply

Your email address will not be published. Required fields are marked *

Maria in Vancouver

Lifestyle4 days ago

Family Estrangement: Why It’s Okay

Family estrangement is the absence of a previously long-standing relationship between family members via emotional or physical distancing to the...

Lifestyle2 months ago

Becoming Your Best Version

By Matter Laurel-Zalko As a woman, I’m constantly evolving. I’m constantly changing towards my better version each year. Actually, I’m...

Lifestyle2 months ago

The True Power of Manifestation

I truly believe in the power of our imagination and that what we believe in our lives is an actual...

Maria in Vancouver3 months ago

DECORATE YOUR HOME 101

By Matte Laurel-Zalko Our home interiors are an insight into our brains and our hearts. It is our own collaboration...

Maria in Vancouver3 months ago

Guide to Planning a Wedding in 2 Months

By Matte Laurel-Zalko Are you recently engaged and find yourself in a bit of a pickle because you and your...

Maria in Vancouver4 months ago

Staying Cool and Stylish this Summer

By Matte Laurel-Zalko I couldn’t agree more when the great late Ella Fitzgerald sang “Summertime and the livin’ is easy.”...

Maria in Vancouver4 months ago

Ageing Gratefully and Joyfully

My 56th trip around the sun is just around the corner! Whew. Wow. Admittedly, I used to be afraid of...

Maria in Vancouver5 months ago

My Love Affair With Pearls

On March 18, 2023, my article, The Power of Pearls was published. In that article, I wrote about the history...

Maria in Vancouver5 months ago

7 Creative Ways to Propose!

Sometime in April 2022, my significant other gave me a heads up: he will be proposing to me on May...

Maria in Vancouver6 months ago

Why Eating Healthy Matters

We are what we eat, so don’t be fast, cheap, easy, or fake — we should take these words to...