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first_img 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 For all that Charles Darwin figured out about life on earth, he was perpetually perplexed by flowering plants, calling their explosive evolution an “abominable mystery.” Now, a newly analyzed fossil species has shed light on where these plants, known as angiosperms, may have gotten their start. In water is the surprising suggestion.For years botanists thought that angiosperms, which came to dominate the terrestrial landscape 160 million years ago, had arisen on dry land as they evolved from existing land plants. Bolstering the idea was the discovery in 1999 that a tiny land-dwelling shrub called Amborella sits at the base of the angiosperm family tree. “The consensus is that [flowering plants] originated on land and moved into water,” says Michael Donoghue, an evolutionary biologist at Yale University.But David Dilcher, a paleobotanist at Indiana University, Bloomington, is now questioning that consensus. After an intense investigation of more than 1000 specimens of the fossil plant Montsechia vidalii, he and a team of researchers have concluded that the 125-million-year-old water dwellers are close relatives of the foxtail plant, a modern angiosperm. The connection between this fossil and the foxtail, as well as evidence from other ancient water plants, indicates that early on—perhaps at their very beginnings—angiosperms thrived in freshwater lakes and ponds, they suggest today in the Proceedings of the National Academy of Sciences. Since Montsechia’s discovery in rock deposits in Spain 150 years ago, botanists have classified it as a horsetail, a conifer, a tropical evergreen tree, and a liverwort, before finally deciding it was a flowering plant. To better understand these fossils, Dilcher and colleagues spent 6 years painstakingly dissolving the limestone surrounding them, revealing intricate structures beneath. The fossil species and current foxtail plants appear to share many of the same traits, Dilcher says. For example, analysis indicated that they are both pollinated underwater. Once released, their pollen sink and grow tubes, one of which eventually links to a hole in the female’s seed-bearing structure, where fertilization occurs and the seed and fruit form.This kinship with foxtail is intriguing, says Dilcher, because in the 1990s, foxtails were widely considered to be at the base of the flowering plants family tree. Then, molecular studies caused them and water lilies—another contender for the base—to give up their title to Amborella.  Dilcher argues it’s time to reassess this assumption about Amborella using new morphological and molecular data.Based on the Montsechia analysis, he wonders whether angiosperms made their first appearance in water. Two things in particular urge him on. If the close connection to Montsechia is true, then the foxtails would be 10 million years older than previously thought, he says, placing them closer to the time when angiosperms originated. In addition, other ancient aquatic angiosperms arose independently around the same time as Montsechia. Water lilies, for example, first made their appearance in Portugal about 125 million years ago. And another “first flower” contender—also an aquatic angiosperm—arose in China 125 million years ago, as Dilcher and his colleagues described in 1998.Dilcher’s most recent work “demonstrates that aquatic angiosperms lived at the same time in very different regions of the Earth, [and that] adaptation to freshwater occurred early in angiosperm evolution,” says Pamela Soltis, a plant biologist at the University of Florida in Gainesville, who was not involved with the work. “The paper offers fresh evidence that early angiosperms invaded freshwater aquatic habitats,” agrees Taylor Feild, a botanist at James Cook University in Townsville, Australia. But he’s not convinced that flowering plants called water their first home. As he and others point out, even though land plants are just as old, aquatic plants are much more likely to be preserved in the fossil record, creating a potential bias.Soltis, too, is skeptical that angiosperms started in water, but she says she is willing to keep an open mind. Finding more fossils of aquatic flowering plants and placing those fossils in the family tree “will tell us whether the first angiosperms were aquatic or terrestrial.” Click to view the privacy policy. Required fields are indicated by an asterisk (*)center_img Email Sign up for our daily newsletter Get more great content like this delivered right to you! Countrylast_img read more