{"id":14478,"date":"2022-06-30T21:33:53","date_gmt":"2022-06-30T21:33:53","guid":{"rendered":"https:\/\/www.lifescienceart.com\/?p=14478"},"modified":"2022-06-30T21:33:53","modified_gmt":"2022-06-30T21:33:53","slug":"dinosaur-extinction-theories-vitamin-d-uv-radiation","status":"publish","type":"post","link":"https:\/\/www.lifescienceart.com\/vi\/science\/paleontology\/dinosaur-extinction-theories-vitamin-d-uv-radiation\/","title":{"rendered":"Gi\u1ea3 thuy\u1ebft v\u1ec1 s\u1ef1 tuy\u1ec7t ch\u1ee7ng c\u1ee7a lo\u00e0i kh\u1ee7ng long: Vai tr\u00f2 c\u1ee7a b\u1ee9c x\u1ea1 tia c\u1ef1c t\u00edm v\u00e0 t\u00ecnh tr\u1ea1ng thi\u1ebfu h\u1ee5t vitamin D"},"content":{"rendered":"

Thuy\u1ebft v\u1ec1 s\u1ef1 tuy\u1ec7t ch\u1ee7ng c\u1ee7a lo\u00e0i kh\u1ee7ng long: Vai tr\u00f2 c\u1ee7a b\u1ee9c x\u1ea1 tia c\u1ef1c t\u00edm v\u00e0 t\u00ecnh tr\u1ea1ng thi\u1ebfu h\u1ee5t vitamin D<\/h2>\n\n

Nh\u1eefng thay \u0111\u1ed5i c\u1ee7a m\u00f4i tr\u01b0\u1eddng v\u00e0 s\u1ef1 tuy\u1ec7t ch\u1ee7ng h\u00e0ng lo\u1ea1t<\/h2>\n\n

S\u1ef1 tuy\u1ec7t ch\u1ee7ng c\u1ee7a lo\u00e0i kh\u1ee7ng long, m\u1ed9t s\u1ef1 ki\u1ec7n th\u1ea3m kh\u1ed1c x\u1ea3y ra c\u00e1ch \u0111\u00e2y 65 tri\u1ec7u n\u0103m, \u0111\u00e3 thu h\u00fat s\u1ef1 ch\u00fa \u00fd c\u1ee7a c\u00e1c nh\u00e0 khoa h\u1ecdc trong nhi\u1ec1u th\u1ebf k\u1ef7. Trong s\u1ed1 r\u1ea5t nhi\u1ec1u gi\u1ea3 thuy\u1ebft \u0111\u01b0\u1ee3c \u0111\u01b0a ra, c\u00f3 m\u1ed9t gi\u1ea3 thuy\u1ebft \u0111\u00e3 g\u00e2y \u0111\u01b0\u1ee3c s\u1ef1 ch\u00fa \u00fd, \u0111\u00f3 l\u00e0 \u00fd ki\u1ebfn cho r\u1eb1ng nh\u1eefng thay \u0111\u1ed5i \u0111\u1ed9t ng\u1ed9t c\u1ee7a m\u00f4i tr\u01b0\u1eddng \u0111\u00e3 \u0111\u00f3ng m\u1ed9t vai tr\u00f2 quan tr\u1ecdng.<\/p>\n\n

Gi\u1ea3 thuy\u1ebft c\u00f2i x\u01b0\u01a1ng c\u1ee7a Harry Marshall<\/h2>\n\n

N\u0103m 1928, nh\u00e0 nghi\u00ean c\u1ee9u b\u1ec7nh h\u1ecdc Harry T. Marshall \u0111\u00e3 \u0111\u01b0a ra m\u1ed9t gi\u1ea3 thuy\u1ebft h\u1ea5p d\u1eabn r\u1eb1ng lo\u00e0i kh\u1ee7ng long c\u00f3 th\u1ec3 \u0111\u00e3 m\u1eafc b\u1ec7nh c\u00f2i x\u01b0\u01a1ng, m\u1ed9t t\u00ecnh tr\u1ea1ng do thi\u1ebfu h\u1ee5t vitamin D. Marshall \u0111\u01b0a ra gi\u1ea3 thuy\u1ebft r\u1eb1ng nh\u1eefng \u0111\u00e1m m\u00e2y b\u1ee5i \u0111\u00e3 che khu\u1ea5t \u00e1nh s\u00e1ng m\u1eb7t tr\u1eddi, c\u1eaft \u0111\u1ee9t ngu\u1ed3n cung c\u1ea5p tia c\u1ef1c t\u00edm (UV) cho lo\u00e0i kh\u1ee7ng long, v\u1ed1n r\u1ea5t c\u1ea7n thi\u1ebft cho qu\u00e1 tr\u00ecnh s\u1ea3n xu\u1ea5t vitamin D.<\/p>\n\n

B\u1eb1ng ch\u1ee9ng v\u1ec1 t\u00ecnh tr\u1ea1ng thi\u1ebfu h\u1ee5t vitamin D<\/h2>\n\n

Gi\u1ea3 thuy\u1ebft c\u1ee7a Marshall \u0111\u00e3 tr\u1edf n\u00ean \u0111\u00e1ng tin c\u1eady h\u01a1n nhi\u1ec1u th\u1eadp k\u1ef7 sau \u0111\u00f3, khi Charles Cockell c\u1ee7a \u0110\u1ea1i h\u1ecdc Stanford \u0111\u00e3 xem x\u00e9t l\u1ea1i \u00fd t\u01b0\u1edfng n\u00e0y trong t\u1ea1p ch\u00ed Paleobiology. Cockell ch\u1ec9 ra r\u1eb1ng d\u01b0\u01a1ng x\u1ec9 v\u00e0 c\u00e1c lo\u1ea1i th\u1ef1c v\u1eadt kh\u00e1c, v\u1ed1n chi\u1ebfm m\u1ed9t ph\u1ea7n \u0111\u00e1ng k\u1ec3 trong ch\u1ebf \u0111\u1ed9 \u0103n c\u1ee7a lo\u00e0i kh\u1ee7ng long, l\u1ea1i kh\u00f4ng c\u00f3 c\u00e1c h\u1ee3p ch\u1ea5t h\u1ea5p th\u1ee5 tia UV. \u0110i\u1ec1u n\u00e0y cho th\u1ea5y lo\u00e0i kh\u1ee7ng long c\u00f3 th\u1ec3 \u0111\u00e3 g\u1eb7p kh\u00f3 kh\u0103n trong vi\u1ec7c h\u1ea5p th\u1ee5 \u0111\u1ee7 vitamin D t\u1eeb ngu\u1ed3n th\u1ee9c \u0103n c\u1ee7a ch\u00fang.<\/p>\n\n

B\u00e1c b\u1ecf gi\u1ea3 thuy\u1ebft v\u1ec1 vi\u1ec7c \u0103n tr\u1ee9ng<\/h2>\n\n

M\u1ed9t gi\u1ea3 thuy\u1ebft ph\u1ed5 bi\u1ebfn nh\u01b0ng sai l\u1ea7m v\u1ec1 s\u1ef1 tuy\u1ec7t ch\u1ee7ng cho r\u1eb1ng nh\u1eefng lo\u00e0i \u0111\u1ed9ng v\u1eadt c\u00f3 v\u00fa nh\u1ecf \u0111\u00e3 \u0103n tr\u1ee9ng kh\u1ee7ng long, d\u1eabn \u0111\u1ebfn s\u1ef1 di\u1ec7t vong c\u1ee7a lo\u00e0i kh\u1ee7ng long. Tuy nhi\u00ean, gi\u1ea3 thuy\u1ebft n\u00e0y kh\u00f4ng t\u00ednh \u0111\u1ebfn s\u1ed1 l\u01b0\u1ee3ng tr\u1ee9ng kh\u1ed5ng l\u1ed3 c\u1ea7n c\u00f3 \u0111\u1ec3 duy tr\u00ec qu\u1ea7n th\u1ec3 \u0111\u1ed9ng v\u1eadt c\u00f3 v\u00fa. Ngo\u00e0i ra, c\u00e1c nh\u00e0 c\u1ed5 sinh v\u1eadt h\u1ecdc c\u0169ng kh\u00f4ng t\u00ecm th\u1ea5y b\u1eb1ng ch\u1ee9ng n\u00e0o v\u1ec1 t\u00ecnh tr\u1ea1ng s\u0103n tr\u1ee9ng tr\u00e0n lan.<\/p>\n\n

T\u00e1c \u0111\u1ed9ng c\u1ee7a b\u1ee9c x\u1ea1 tia c\u1ef1c t\u00edm<\/h2>\n\n

Cockell \u0111\u00e3 \u0111\u01b0a gi\u1ea3 thuy\u1ebft c\u1ee7a Marshall ti\u1ebfn xa h\u01a1n m\u1ed9t b\u01b0\u1edbc khi cho r\u1eb1ng b\u1ee9c x\u1ea1 tia c\u1ef1c t\u00edm qu\u00e1 m\u1ee9c, do s\u1ef1 suy gi\u1ea3m \u0111\u1ecbnh k\u1ef3 c\u1ee7a t\u1ea7ng ozone, c\u00f3 th\u1ec3 l\u00e0 nguy\u00ean nh\u00e2n g\u00e2y ra s\u1ef1 tuy\u1ec7t ch\u1ee7ng h\u00e0ng lo\u1ea1t. B\u1ee9c x\u1ea1 tia c\u1ef1c t\u00edm c\u00f3 th\u1ec3 l\u00e0m h\u1ecfng DNA v\u00e0 \u1ee9c ch\u1ebf h\u1ec7 th\u1ed1ng mi\u1ec5n d\u1ecbch, khi\u1ebfn c\u00e1c sinh v\u1eadt d\u1ec5 b\u1ecb t\u1ed5n th\u01b0\u01a1ng h\u01a1n tr\u01b0\u1edbc b\u1ec7nh t\u1eadt v\u00e0 c\u00e1c t\u00e1c nh\u00e2n g\u00e2y c\u0103ng th\u1eb3ng t\u1eeb m\u00f4i tr\u01b0\u1eddng.<\/p>\n\n

B\u1eb1ng ch\u1ee9ng v\u1ec1 s\u1ef1 suy gi\u1ea3m t\u1ea7ng ozone<\/h2>\n\n

M\u1eb7c d\u00f9 gi\u1ea3 thuy\u1ebft v\u1ec1 s\u1ef1 suy gi\u1ea3m t\u1ea7ng ozone v\u1eabn c\u00f2n mang t\u00ednh ph\u1ecfng \u0111o\u00e1n, nh\u01b0ng c\u00f3 b\u1eb1ng ch\u1ee9ng cho th\u1ea5y n\u00f3 c\u00f3 th\u1ec3 \u0111\u00e3 \u0111\u00f3ng m\u1ed9t vai tr\u00f2 nh\u1ea5t \u0111\u1ecbnh. C\u00e1c nghi\u00ean c\u1ee9u \u0111\u00e3 ch\u1ec9 ra r\u1eb1ng trong K\u1ef7 Ph\u1ea5n tr\u1eafng, t\u1ea7ng ozone m\u1ecfng h\u01a1n hi\u1ec7n nay, cho ph\u00e9p nhi\u1ec1u b\u1ee9c x\u1ea1 tia c\u1ef1c t\u00edm h\u01a1n \u0111\u1ebfn b\u1ec1 m\u1eb7t Tr\u00e1i \u0111\u1ea5t.<\/p>\n\n

Nghi\u00ean c\u1ee9u \u0111ang ti\u1ebfp di\u1ec5n v\u00e0 nh\u1eefng h\u1ec7 qu\u1ea3<\/h2>\n\n

Nh\u1eefng gi\u1ea3 thuy\u1ebft xung quanh s\u1ef1 tuy\u1ec7t ch\u1ee7ng c\u1ee7a lo\u00e0i kh\u1ee7ng long v\u1eabn li\u00ean t\u1ee5c \u0111\u01b0\u1ee3c c\u00e1c nh\u00e0 khoa h\u1ecdc tinh ch\u1ec9nh v\u00e0 tranh lu\u1eadn. Gi\u1ea3 thuy\u1ebft ban \u0111\u1ea7u c\u1ee7a Marshall v\u00e0 qu\u00e1 tr\u00ecnh kh\u00e1m ph\u00e1 b\u1ee9c x\u1ea1 tia c\u1ef1c t\u00edm sau \u0111\u00f3 c\u1ee7a Cockell \u0111\u00e3 cung c\u1ea5p nh\u1eefng hi\u1ec3u bi\u1ebft c\u00f3 gi\u00e1 tr\u1ecb v\u1ec1 c\u00e1c y\u1ebfu t\u1ed1 m\u00f4i tr\u01b0\u1eddng ti\u1ec1m \u1ea9n c\u00f3 th\u1ec3 \u0111\u00e3 g\u00f3p ph\u1ea7n v\u00e0o s\u1ef1 ki\u1ec7n th\u1ea3m kh\u1ed1c n\u00e0y.<\/p>\n\n

T\u1ea7m quan tr\u1ecdng c\u1ee7a vitamin D<\/h2>\n\n

T\u00ecnh tr\u1ea1ng thi\u1ebfu h\u1ee5t vitamin D c\u00f3 li\u00ean quan \u0111\u1ebfn nhi\u1ec1u v\u1ea5n \u0111\u1ec1 s\u1ee9c kh\u1ecfe \u1edf c\u00e1c lo\u00e0i \u0111\u1ed9ng v\u1eadt hi\u1ec7n \u0111\u1ea1i, bao g\u1ed3m bi\u1ebfn d\u1ea1ng x\u01b0\u01a1ng, y\u1ebfu c\u01a1 v\u00e0 r\u1ed1i lo\u1ea1n ch\u1ee9c n\u0103ng h\u1ec7 th\u1ed1ng mi\u1ec5n d\u1ecbch. C\u00f3 kh\u1ea3 n\u0103ng l\u00e0 nh\u1eefng v\u1ea5n \u0111\u1ec1 s\u1ee9c kh\u1ecfe t\u01b0\u01a1ng t\u1ef1 c\u0169ng \u0111\u00e3 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn lo\u00e0i kh\u1ee7ng long trong nh\u1eefng th\u1eddi k\u1ef3 ti\u1ebfp x\u00fac v\u1edbi tia UV h\u1ea1n ch\u1ebf.<\/p>\n\n

Nh\u1eefng thay \u0111\u1ed5i c\u1ee7a m\u00f4i tr\u01b0\u1eddng v\u00e0 s\u1ef1 tuy\u1ec7t ch\u1ee7ng trong t\u01b0\u01a1ng lai<\/h2>\n\n

Nghi\u00ean c\u1ee9u c\u00e1c gi\u1ea3 thuy\u1ebft v\u1ec1 s\u1ef1 tuy\u1ec7t ch\u1ee7ng c\u1ee7a lo\u00e0i kh\u1ee7ng long c\u00f3 \u00fd ngh\u0129a \u0111\u1ed1i v\u1edbi vi\u1ec7c hi\u1ec3u \u0111\u01b0\u1ee3c nh\u1eefng t\u00e1c \u0111\u1ed9ng ti\u1ec1m \u1ea9n c\u1ee7a nh\u1eefng thay \u0111\u1ed5i m\u00f4i tr\u01b0\u1eddng \u0111\u1ed1i v\u1edbi c\u00e1c lo\u00e0i hi\u1ec7n \u0111\u1ea1i. Khi c\u00e1c ho\u1ea1t \u0111\u1ed9ng c\u1ee7a con ng\u01b0\u1eddi ti\u1ebfp t\u1ee5c l\u00e0m thay \u0111\u1ed5i h\u1ec7 sinh th\u00e1i c\u1ee7a h\u00e0nh tinh, \u0111i\u1ec1u c\u1ea7n thi\u1ebft l\u00e0 ph\u1ea3i c\u00e2n nh\u1eafc \u0111\u1ebfn nh\u1eefng c\u00e1ch m\u00e0 nh\u1eefng thay \u0111\u1ed5i n\u00e0y c\u00f3 th\u1ec3 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn s\u1ee9c kh\u1ecfe v\u00e0 s\u1ef1 t\u1ed3n vong c\u1ee7a c\u1ea3 th\u1ef1c v\u1eadt v\u00e0 \u0111\u1ed9ng v\u1eadt.<\/p>","protected":false},"excerpt":{"rendered":"

Thuy\u1ebft v\u1ec1 s\u1ef1 tuy\u1ec7t ch\u1ee7ng c\u1ee7a lo\u00e0i kh\u1ee7ng long: Vai tr\u00f2 c\u1ee7a b\u1ee9c x\u1ea1 tia c\u1ef1c t\u00edm v\u00e0 t\u00ecnh tr\u1ea1ng thi\u1ebfu h\u1ee5t vitamin D Nh\u1eefng thay \u0111\u1ed5i c\u1ee7a m\u00f4i tr\u01b0\u1eddng…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[138],"tags":[137,134,19436,400,19435],"class_list":["post-14478","post","type-post","status-publish","format-standard","hentry","category-paleontology","tag-paleontology","tag-dinosaurs","tag-uv-radiation","tag-extinction","tag-vitamin-d"],"_links":{"self":[{"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/posts\/14478","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/comments?post=14478"}],"version-history":[{"count":1,"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/posts\/14478\/revisions"}],"predecessor-version":[{"id":14479,"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/posts\/14478\/revisions\/14479"}],"wp:attachment":[{"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/media?parent=14478"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/categories?post=14478"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lifescienceart.com\/vi\/wp-json\/wp\/v2\/tags?post=14478"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}