293:
951:
24:
324:
963:
201:. These eggs had microstructures identical to those of modern crocodiles. This suggests that once the crocodilian's rigid eggshell first evolved it changed very little over time. Crocodilian eggshell is regarded as primitive because it only contains one type of calcite crystal and these crystals are arranged in "tight columns".
148:
The earliest reptile eggshells probably had leathery membranes instead of hard shells. Eggs like this decay so quickly that fossilization is very unlikely. Therefore, the fossil record is too incomplete for scientists to determine what kinds of eggshell most fossil reptile groups had. A 5.9 cm
271:
formations. No modern reptile is known to lay their eggs on the seafloor, so these eggs likely originated in a different environmental setting. Ken
Carpenter notes that while it's not possible to be completely sure how these eggs ended up on the seabed, some possibilities include carcasses of dead
223:
dinosaurs' eggshell microstructure are so similar to modern birds that its almost impossible to distinguish the two. These very bird-like eggs are only referred to non-avian dinosaurs due to their size and age. Bird eggshell microstructure is complex and more similar to theropod dinosaurs than to
276:
females being washed out to sea and releasing its eggs when by splitting open, carried out to sea by floods, or drifting out on mats of vegetation. At least two clutches of hard-shelled turtle eggs preserved in volcanic ash are known from the
169:
in the object's outer layer to propose that the fossil was actually an egg with a leathery shell. If the contentious fossil really is a reptile egg, it's the oldest known.
161:
as the oldest hard-shelled fossil egg. However, in a 1979 paper Karl Hirsch disputed Romer and Price's claim, since the fossil in question didn't show evidence for a
34:
132:, reptilian eggs may go back significantly farther than their fossil record. Many ancient reptile groups are known from egg fossils including
259:
of the western US. Fully rigid turtle eggshell is known from Late
Jurassic strata in Portugal. Fossil turtle eggs are known from the marine
140:, and turtles. Some ancient reptiles are known to have given live birth and are therefore not anticipated to have left behind egg fossils.
424:
92:
316:
64:
452:
49:
71:
78:
904:
821:
706:
60:
899:
129:
512:
306:
989:
854:
260:
158:
298:
248:
242:
849:
676:
532:
470:
445:
256:
225:
85:
909:
653:
420:
264:
967:
268:
781:
608:
563:
517:
328:
311:
237:
194:; however, the rigid eggshell itself was probably much older than these specific fossils.
919:
869:
864:
839:
791:
711:
278:
191:
983:
955:
879:
829:
686:
598:
438:
253:
187:
150:
125:
124:
laid by reptiles. The fossil record of reptile eggs goes back at least as far as the
796:
756:
746:
681:
668:
526:
417:
Eggs, Nests, and Baby
Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past)
210:
198:
183:
154:
936:
931:
926:
761:
751:
716:
701:
696:
618:
548:
128:. However, since the earliest reptile eggs probably had soft shells with little
23:
219:
eggshell was so resilient that it is the most common kind of egg fossils. Some
874:
844:
834:
806:
801:
786:
691:
504:
288:
166:
133:
117:
41:
776:
726:
644:
613:
603:
593:
573:
494:
197:
The oldest known fossil crocodilian eggs are from Early
Cretaceous rocks of
224:
crocodilians. The commonality in eggshell structure is more evidence that
884:
741:
736:
731:
649:
553:
484:
220:
216:
137:
914:
894:
811:
658:
588:
578:
162:
889:
859:
766:
721:
623:
568:
558:
273:
583:
281:. These eggs were likely buried in the debris by large tortoises.
639:
434:
771:
489:
461:
385:"Evolution of the Reptile Egg," Carpenter (1999); pages 44–45.
121:
17:
252:. There are also semi-rigid turtle eggshells known from the
394:"Evolution of the Reptile Egg," Carpenter (1999); page 45.
376:"Evolution of the Reptile Egg," Carpenter (1999); page 47.
367:"Evolution of the Reptile Egg," Carpenter (1999); page 46.
355:"Evolution of the Reptile Egg," Carpenter (1999); page 44.
346:"Evolution of the Reptile Egg," Carpenter (1999); page 43.
236:
The oldest known semi-rigid fossil eggshells date to the
430:
45:
403:"How to Fossilize an Egg," Carpenter (1999); page 112.
215:
The eggs of the earliest dinosaurs are poorly known.
820:
667:
632:
541:
503:
477:
363:
361:
240:of England. The egg specimen was originally called
182:The earliest known fossil rigid eggs were laid by
446:
8:
50:introducing citations to additional sources
453:
439:
431:
173:Reptile groups with documented fossil eggs
40:Relevant discussion may be found on the
339:
7:
962:
14:
961:
950:
949:
322:
291:
149:by 3.79 cm fossil from the
33:relies largely or entirely on a
22:
317:Timeline of egg fossil research
1:
419:, Indiana University Press;
226:birds evolved from theropods
415:Carpenter, Kenneth (1999).
165:shell. Hirsch found enough
1006:
208:
945:
468:
153:was described in 1939 by
186:crocodilians during the
144:Evolution and diversity
130:preservation potential
307:Cephalopod egg fossil
855:Egg drop competition
61:"Reptile egg fossil"
46:improve this article
329:Reptiles portal
299:Paleontology portal
249:Testudoflexoolithus
243:Oolithes bathonicae
114:Reptile egg fossils
850:Egg-and-spoon race
677:List of egg dishes
490:Fish and amphibian
471:List of egg topics
257:Morrison Formation
977:
976:
910:Ovo vegetarianism
265:Stonesfield Slate
111:
110:
96:
997:
965:
964:
953:
952:
707:Custard desserts
455:
448:
441:
432:
404:
401:
395:
392:
386:
383:
377:
374:
368:
365:
356:
353:
347:
344:
327:
326:
325:
301:
296:
295:
294:
269:Mooreville Chalk
106:
103:
97:
95:
54:
26:
18:
1005:
1004:
1000:
999:
998:
996:
995:
994:
980:
979:
978:
973:
941:
816:
663:
628:
564:Ichthyoplankton
537:
499:
473:
464:
459:
412:
407:
402:
398:
393:
389:
384:
380:
375:
371:
366:
359:
354:
350:
345:
341:
337:
323:
321:
312:Fish egg fossil
297:
292:
290:
287:
261:White Limestone
238:Middle Jurassic
234:
213:
207:
180:
175:
146:
107:
101:
98:
55:
53:
39:
27:
12:
11:
5:
1003:
1001:
993:
992:
982:
981:
975:
974:
972:
971:
959:
946:
943:
942:
940:
939:
934:
929:
924:
923:
922:
920:Vegreville egg
912:
907:
902:
897:
892:
887:
882:
877:
872:
867:
862:
857:
852:
847:
842:
837:
832:
826:
824:
818:
817:
815:
814:
809:
804:
799:
794:
789:
784:
779:
774:
769:
764:
759:
754:
749:
744:
739:
734:
729:
724:
719:
714:
709:
704:
699:
694:
689:
684:
679:
673:
671:
665:
664:
662:
661:
656:
647:
642:
636:
634:
630:
629:
627:
626:
621:
616:
611:
606:
601:
596:
591:
586:
581:
576:
571:
566:
561:
556:
551:
545:
543:
539:
538:
536:
535:
530:
520:
515:
509:
507:
501:
500:
498:
497:
492:
487:
481:
479:
475:
474:
469:
466:
465:
460:
458:
457:
450:
443:
435:
429:
428:
411:
408:
406:
405:
396:
387:
378:
369:
357:
348:
338:
336:
333:
332:
331:
319:
314:
309:
303:
302:
286:
283:
279:Canary Islands
246:, but renamed
233:
230:
209:Main article:
206:
203:
192:Early Jurassic
179:
176:
174:
171:
159:Lewellyn Price
145:
142:
109:
108:
44:. Please help
30:
28:
21:
13:
10:
9:
6:
4:
3:
2:
1002:
991:
988:
987:
985:
970:
969:
960:
958:
957:
948:
947:
944:
938:
935:
933:
930:
928:
925:
921:
918:
917:
916:
913:
911:
908:
906:
905:Organizations
903:
901:
898:
896:
893:
891:
888:
886:
883:
881:
880:Humpty Dumpty
878:
876:
873:
871:
868:
866:
863:
861:
858:
856:
853:
851:
848:
846:
843:
841:
838:
836:
833:
831:
828:
827:
825:
823:
819:
813:
810:
808:
805:
803:
800:
798:
795:
793:
790:
788:
785:
783:
780:
778:
775:
773:
770:
768:
765:
763:
760:
758:
755:
753:
750:
748:
745:
743:
740:
738:
735:
733:
730:
728:
725:
723:
720:
718:
715:
713:
710:
708:
705:
703:
700:
698:
695:
693:
690:
688:
685:
683:
680:
678:
675:
674:
672:
670:
666:
660:
657:
655:
651:
648:
646:
643:
641:
638:
637:
635:
631:
625:
622:
620:
617:
615:
612:
610:
607:
605:
602:
600:
599:Ovoviviparity
597:
595:
592:
590:
587:
585:
582:
580:
577:
575:
572:
570:
567:
565:
562:
560:
557:
555:
552:
550:
547:
546:
544:
540:
534:
531:
528:
524:
521:
519:
516:
514:
511:
510:
508:
506:
505:Fossil record
502:
496:
493:
491:
488:
486:
483:
482:
480:
476:
472:
467:
463:
456:
451:
449:
444:
442:
437:
436:
433:
426:
425:0-253-33497-7
422:
418:
414:
413:
409:
400:
397:
391:
388:
382:
379:
373:
370:
364:
362:
358:
352:
349:
343:
340:
334:
330:
320:
318:
315:
313:
310:
308:
305:
304:
300:
289:
284:
282:
280:
275:
270:
266:
262:
258:
255:
254:Late Jurassic
251:
250:
245:
244:
239:
231:
229:
227:
222:
218:
212:
204:
202:
200:
195:
193:
189:
188:Late Triassic
185:
184:South African
177:
172:
170:
168:
164:
160:
156:
152:
151:Lower Permian
143:
141:
139:
135:
131:
127:
126:Early Permian
123:
119:
115:
105:
102:November 2015
94:
91:
87:
84:
80:
77:
73:
70:
66:
63: –
62:
58:
57:Find sources:
51:
47:
43:
37:
36:
35:single source
31:This article
29:
25:
20:
19:
16:
966:
954:
747:Onsen tamago
522:
416:
399:
390:
381:
372:
351:
342:
247:
241:
235:
214:
211:Dinosaur egg
199:Galve, Spain
196:
181:
178:Crocodilians
155:Alfred Romer
147:
134:crocodilians
113:
112:
99:
89:
82:
75:
68:
56:
32:
15:
990:Egg fossils
865:Fabergé egg
120:remains of
875:HowToBasic
870:Free range
845:Easter egg
840:Decorating
822:In culture
712:Deep fried
633:Components
513:Cephalopod
410:References
167:phosphorus
118:fossilized
72:newspapers
830:Balancing
792:Scrambled
604:Ovulation
594:Oviparity
574:Oogenesis
533:Pathology
495:Monotreme
335:Footnotes
205:Dinosaurs
138:dinosaurs
42:talk page
984:Category
956:Category
757:Powdered
742:Omelette
737:Meringue
687:Benedict
654:membrane
554:Egg cell
527:dinosaur
285:See also
221:theropod
217:Dinosaur
116:are the
968:Commons
937:Tossing
932:Tapping
927:Rolling
915:Pysanka
900:Organic
895:Oomancy
807:Soufflé
797:Shirred
762:Pickled
752:Poached
717:Deviled
702:Coddled
697:Century
669:As food
659:Chalaza
619:Trophic
589:Oviduct
579:Ootheca
549:Allergy
542:Biology
523:Reptile
232:Turtles
163:calcite
86:scholar
890:Oology
860:Egging
835:Carton
802:Smoked
787:Scotch
782:Salted
767:Quiche
722:Eggnog
692:Boiled
624:Zygote
569:Oogamy
559:Embryo
423:
274:gravid
267:, and
88:
81:
74:
67:
59:
777:Salad
727:Fried
682:Balut
650:Shell
645:White
614:Tooth
609:Spawn
584:Ovary
478:Types
93:JSTOR
79:books
885:Hunt
732:Iron
652:and
640:Yolk
518:Fish
485:Bird
462:Eggs
421:ISBN
157:and
122:eggs
65:news
812:Tea
772:Roe
190:or
48:by
986::
360:^
263:,
228:.
136:,
529:)
525:(
454:e
447:t
440:v
427:.
104:)
100:(
90:·
83:·
76:·
69:·
52:.
38:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
