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minerva-icon--edit"></span> <span>Edit</span> </a> </li> </ul> </nav>  <div id="mw-content-subtitle"></div> </div> <div id="bodyContent" class="content"> <div id="mw-content-text" class="mw-body-content"><script>function mfTempOpenSection(id){var block=document.getElementById("mf-section-"+id);block.className+=" open-block";block.previousSibling.className+=" open-block";}</script><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><section class="mf-section-0" id="mf-section-0"> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">"YBP" and "ybp" redirect here. For other uses, see <a href="/wiki/YBP_(disambiguation)" class="mw-disambig" title="YBP (disambiguation)">YBP (disambiguation)</a>.</div> <p><b>Before Present</b> (<b>BP</b>) or "<b>years before present</b> (<b>YBP</b>)" is a <a href="/wiki/Geologic_time_scale" title="Geologic time scale">time scale</a> used mainly in <a href="/wiki/Archaeology" title="Archaeology">archaeology</a>, geology, and other scientific disciplines to specify when events occurred relative to the origin of practical <a href="/wiki/Radiocarbon_dating" title="Radiocarbon dating">radiocarbon dating</a> in the 1950s. Because the "present" time changes, standard practice is to use 1 January 1950 as the commencement date (epoch) of the age scale, with 1950 being labelled as the "standard year". The abbreviation "BP" has been interpreted retrospectively as "Before Physics",<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> which refers to the time before <a href="/wiki/Nuclear_weapons_testing" title="Nuclear weapons testing">nuclear weapons testing</a> artificially altered the proportion of the <a href="/wiki/Isotopes_of_carbon" title="Isotopes of carbon">carbon isotopes</a> in the atmosphere, which scientists must account for.<sup id="cite_ref-Taylor_3-0" class="reference"><a href="#cite_note-Taylor-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>In a convention that is not always observed, many sources restrict the use of BP dates to those produced with radiocarbon dating; the alternative notation "RCYBP" stands for the explicit "radio carbon years before present". </p> <div id="toc" class="toc" role="navigation" aria-labelledby="mw-toc-heading"><input type="checkbox" role="button" id="toctogglecheckbox" class="toctogglecheckbox" style="display:none"><div class="toctitle" lang="en" dir="ltr"><h2 id="mw-toc-heading">Contents</h2><span class="toctogglespan"><label class="toctogglelabel" for="toctogglecheckbox"></label></span></div> <ul> <li class="toclevel-1 tocsection-1"><a href="#Usage"><span class="tocnumber">1</span> <span class="toctext">Usage</span></a> <ul> <li class="toclevel-2 tocsection-2"><a href="#SI_prefixes"><span class="tocnumber">1.1</span> <span class="toctext">SI prefixes</span></a></li> </ul> </li> <li class="toclevel-1 tocsection-3"><a href="#Radiocarbon_dating"><span class="tocnumber">2</span> <span class="toctext">Radiocarbon dating</span></a></li> <li class="toclevel-1 tocsection-4"><a href="#Radiocarbon_calibration"><span class="tocnumber">3</span> <span class="toctext">Radiocarbon calibration</span></a></li> <li class="toclevel-1 tocsection-5"><a href="#Conversion"><span class="tocnumber">4</span> <span class="toctext">Conversion</span></a></li> <li class="toclevel-1 tocsection-6"><a href="#See_also"><span class="tocnumber">5</span> <span class="toctext">See also</span></a></li> <li class="toclevel-1 tocsection-7"><a href="#Citations"><span class="tocnumber">6</span> <span class="toctext">Citations</span></a></li> <li class="toclevel-1 tocsection-8"><a href="#Sources"><span class="tocnumber">7</span> <span class="toctext">Sources</span></a></li> </ul> </div> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(1)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Usage">Usage</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Before_Present&action=edit&section=1" title="Edit section: Usage" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-1 collapsible-block" id="mf-section-1"> <p>The BP scale is sometimes used for dates established by means other than radiocarbon dating, such as <a href="/wiki/Stratigraphy" title="Stratigraphy">stratigraphy</a>.<sup id="cite_ref-AGUStyle_5-0" class="reference"><a href="#cite_note-AGUStyle-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Strat_6-0" class="reference"><a href="#cite_note-Strat-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> This usage differs from the recommendation by van der Plicht & Hogg,<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> followed by the <i>Quaternary Science Reviews</i>,<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> both of which requested that publications should use the <a href="/wiki/A_(unit)" class="mw-redirect" title="A (unit)">unit "a"</a> (for "annum", Latin for "year") and reserve the term "BP" for radiocarbon estimations. </p><p>Some <a href="/wiki/Archaeologist" class="mw-redirect" title="Archaeologist">archaeologists</a> use the lowercase letters <i>bp</i>, <i><a href="/wiki/Anno_Domini" title="Anno Domini">bc</a></i> and <i><a href="/wiki/Anno_Domini" title="Anno Domini">ad</a></i> as terminology for uncalibrated dates for these eras.<sup id="cite_ref-Huth1994_10-0" class="reference"><a href="#cite_note-Huth1994-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p><p>The Centre for Ice and Climate at the <a href="/wiki/University_of_Copenhagen" title="University of Copenhagen">University of Copenhagen</a> instead uses the unambiguous "b2k", for "years before 2000 AD", often in combination with the <a href="/wiki/Greenland" title="Greenland">Greenland</a> <a href="/wiki/Ice_Core" class="mw-redirect" title="Ice Core">Ice Core</a> Chronology 2005 (GICC05) time scale.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p><p>Some authors who use the YBP dating format also use "YAP" ("years after present") to denote years after 1950.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="SI_prefixes">SI prefixes</h3><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Before_Present&action=edit&section=2" title="Edit section: SI prefixes" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div> <p><a href="/wiki/Metric_prefix" title="Metric prefix">SI prefix multipliers</a> may be used to express larger periods of time, e.g. <i>ka BP</i> (thousand years BP), <i>Ma BP</i> (million years BP) and <a href="/wiki/Year#SI_prefix_multipliers" title="Year">many others</a>.<sup id="cite_ref-Nways_13-0" class="reference"><a href="#cite_note-Nways-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> </p> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(2)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Radiocarbon_dating">Radiocarbon dating</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Before_Present&action=edit&section=3" title="Edit section: Radiocarbon dating" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-2 collapsible-block" id="mf-section-2"> <p><a href="/wiki/Radiocarbon_dating" title="Radiocarbon dating">Radiocarbon dating</a> was first used in 1949.<sup id="cite_ref-libby49_14-0" class="reference"><a href="#cite_note-libby49-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Aitken_60_15-0" class="reference"><a href="#cite_note-Aitken_60-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> Beginning in 1954, <a href="/wiki/Metrologist" class="mw-redirect" title="Metrologist">metrologists</a> established 1950 as the origin year for the BP scale for use with radiocarbon dating, using a 1950-based reference sample of <a href="/wiki/Oxalic_acid" title="Oxalic acid">oxalic acid</a>. According to scientist A. Currie Lloyd: </p> <style data-mw-deduplicate="TemplateStyles:r1244412712">.mw-parser-output .templatequote{overflow:hidden;margin:1em 0;padding:0 32px}.mw-parser-output .templatequotecite{line-height:1.5em;text-align:left;margin-top:0}@media(min-width:500px){.mw-parser-output .templatequotecite{padding-left:1.6em}}</style><blockquote class="templatequote"><p>The problem was tackled by the international radiocarbon community in the late 1950s, in cooperation with the U.S. <a href="/wiki/National_Bureau_of_Standards" class="mw-redirect" title="National Bureau of Standards">National Bureau of Standards</a>. A large quantity of contemporary <a href="/wiki/Oxalic_acid" title="Oxalic acid">oxalic acid</a> <a href="/wiki/Dihydrate" class="mw-redirect" title="Dihydrate">dihydrate</a> was prepared as NBS Standard Reference Material (SRM) 4990B. Its <sup>14</sup>C concentration was about 5% above what was believed to be the natural level, so the standard for radiocarbon dating was defined as 0.95 times the <sup>14</sup>C concentration of this material, adjusted to a <sup>13</sup>C reference value of −19 per mil (PDB). This value is defined as "modern carbon" referenced to AD 1950. Radiocarbon measurements are compared to this modern carbon value, and expressed as "fraction of modern" (fM). "Radiocarbon ages" are calculated from fM using the exponential decay relation and the "Libby half-life" 5568 a. The ages are expressed in years before present (BP) where "present" is defined as AD 1950.<sup id="cite_ref-Currie_16-0" class="reference"><a href="#cite_note-Currie-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup></p></blockquote> <p>The year 1950 was chosen because it was the standard <a href="/wiki/Astronomical_epoch" class="mw-redirect" title="Astronomical epoch">astronomical epoch</a> at that time.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (November 2021)">citation needed</span></a></i>]</sup> It also marked<sup id="cite_ref-Taylor_3-1" class="reference"><a href="#cite_note-Taylor-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> the publication of the first radiocarbon dates in December 1949,<sup id="cite_ref-Arnold_17-0" class="reference"><a href="#cite_note-Arnold-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> and 1950 also antedates large-scale <a href="/wiki/Nuclear_testing" class="mw-redirect" title="Nuclear testing">atmospheric testing of nuclear weapons</a>, which altered the global ratio of <a href="/wiki/Carbon-14" title="Carbon-14">carbon-14</a> to <a href="/wiki/Carbon-12" title="Carbon-12">carbon-12</a>.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> </p> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(3)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Radiocarbon_calibration">Radiocarbon calibration</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Before_Present&action=edit&section=4" title="Edit section: Radiocarbon calibration" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-3 collapsible-block" id="mf-section-3"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Radiocarbon_dating#Calibration" title="Radiocarbon dating">Radiocarbon dating § Calibration</a></div> <p>Dates determined using radiocarbon dating come as two kinds: <i>uncalibrated</i> (also called <i>Libby</i> or <i>raw</i>) and <i>calibrated</i> (also called <i>Cambridge</i>) dates.<sup id="cite_ref-Archaeology_19-0" class="reference"><a href="#cite_note-Archaeology-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> <i>Uncalibrated</i> radiocarbon dates should be clearly noted as such by "uncalibrated years BP", because they are not identical to calendar dates. This has to do with the fact that the level of atmospheric radiocarbon (<a href="/wiki/Carbon-14" title="Carbon-14">carbon-14</a> or <sup>14</sup>C) has not been strictly constant during the span of time that can be radiocarbon-dated. Uncalibrated radiocarbon ages can be converted to calendar dates by <a href="/wiki/Radiocarbon_dating#Calibration" title="Radiocarbon dating">calibration curves</a> based on comparison of raw radiocarbon dates of samples independently dated by other methods, such as <a href="/wiki/Dendrochronology" title="Dendrochronology">dendrochronology</a> (dating based on tree growth-rings) and stratigraphy (dating based on sediment layers in mud or sedimentary rock). Such calibrated dates are expressed as cal BP, where "cal" indicates "calibrated years", or "calendar years", before 1950. </p><p>Many scholarly and scientific journals require that published calibrated results be accompanied by the name (standard codes are used) of the laboratory concerned, and other information such as confidence levels, because of differences between the methods used by different laboratories and changes in calibrating methods. </p> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(4)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Conversion">Conversion</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Before_Present&action=edit&section=5" title="Edit section: Conversion" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-4 collapsible-block" id="mf-section-4"> <p>Conversion from <a href="/wiki/Gregorian_calendar" title="Gregorian calendar">Gregorian calendar</a> years to Before Present years is by starting with the 1950-01-01 epoch of the Gregorian calendar and increasing the BP year count with each year into the past from that Gregorian date. </p><p>For example, 1000 BP corresponds to 950 AD, 1949 BP corresponds to 1 AD, 1950 BP corresponds to 1 BC, 2000 BP corresponds to 51 BC. </p> <table class="wikitable"> <caption>Example milestone years in the BP time scale </caption> <tbody><tr> <th><span class="nowrap">Gregorian year</span> </th> <th><span class="nowrap">BP year</span> </th> <th>Event </th></tr> <tr> <td><a href="/wiki/10th_millennium_BC" title="10th millennium BC">9701 BC</a> </td> <td><span class="nowrap">11650 BP</span> </td> <td>End of the <a href="/wiki/Pleistocene" title="Pleistocene">Pleistocene</a> and beginning of the <a href="/wiki/Holocene" title="Holocene">Holocene</a> epoch<sup id="cite_ref-jqs_20-0" class="reference"><a href="#cite_note-jqs-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td><a href="/wiki/5th_millennium_BC" title="5th millennium BC">4714 BC</a> </td> <td>6663 BP </td> <td><a href="/wiki/Epoch_(reference_date)" class="mw-redirect" title="Epoch (reference date)">Epoch</a> of the <a href="/wiki/Julian_day" title="Julian day">Julian day</a> system: Julian day 0 starts at <a href="/wiki/Prime_meridian_(Greenwich)" title="Prime meridian (Greenwich)">Greenwich</a> noon on January 1, 4713 BC of the <a href="/wiki/Proleptic_Julian_calendar" title="Proleptic Julian calendar">proleptic Julian calendar</a>, which is November 24, 4714 BC in the <a href="/wiki/Proleptic_Gregorian_calendar" title="Proleptic Gregorian calendar">proleptic Gregorian calendar</a><sup id="cite_ref-Dershowitz_21-0" class="reference"><a href="#cite_note-Dershowitz-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 10">: 10 </span></sup> </td></tr> <tr> <td><a href="/wiki/2251_BC" class="mw-redirect" title="2251 BC">2251 BC</a> </td> <td>4200 BP </td> <td>Beginning of the <a href="/wiki/Meghalayan" title="Meghalayan">Meghalayan</a> age, the current and latest of the three stages in the <a href="/wiki/Holocene" title="Holocene">Holocene</a> era.<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td><a href="/wiki/45_BC" title="45 BC">45 BC</a> </td> <td>1994 BP </td> <td>Introduction of the <a href="/wiki/Julian_calendar" title="Julian calendar">Julian calendar</a> </td></tr> <tr> <td><a href="/wiki/1_BC" title="1 BC">1 BC</a> </td> <td>1950 BP </td> <td><a href="/wiki/Year_zero" title="Year zero">Year zero</a> in <a href="/wiki/ISO_8601" title="ISO 8601">ISO 8601</a> </td></tr> <tr> <td><a href="/wiki/AD_1" title="AD 1">AD 1</a> </td> <td>1949 BP </td> <td>Beginning of the <a href="/wiki/Common_Era" title="Common Era">Common Era</a> and <a href="/wiki/Anno_Domini" title="Anno Domini">Anno Domini</a>, from the estimate by <a href="/wiki/Dionysius_Exiguus" title="Dionysius Exiguus">Dionysius</a> of the <a href="/wiki/Incarnation_(Christianity)" title="Incarnation (Christianity)">Incarnation of Jesus</a> </td></tr> <tr> <td>1582 </td> <td>368 BP </td> <td>Introduction of the <a href="/wiki/Gregorian_calendar" title="Gregorian calendar">Gregorian calendar</a><sup id="cite_ref-Dershowitz_21-1" class="reference"><a href="#cite_note-Dershowitz-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 47">: 47 </span></sup> </td></tr> <tr> <td>1950 </td> <td>0000 AP </td> <td><a href="/wiki/Epoch_(reference_date)" class="mw-redirect" title="Epoch (reference date)">Epoch</a> of the Before Present dating scheme<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 190">: 190 </span></sup> </td></tr> <tr> <td>2024 </td> <td>0074 AP </td> <td>Current year </td></tr></tbody></table> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-lower-alpha"> </div> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(5)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="See_also">See also</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Before_Present&action=edit&section=6" title="Edit section: See also" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-5 collapsible-block" id="mf-section-5"> <ul><li><a href="/wiki/Anthropocene" title="Anthropocene">Anthropocene</a></li></ul> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(6)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Citations">Citations</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Before_Present&action=edit&section=7" title="Edit section: Citations" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-6 collapsible-block" id="mf-section-6"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFFlintDeevey1962" class="citation journal cs1">Flint, Richard Foster; Deevey, Edward S (1962). <a rel="nofollow" class="external text" href="https://journals.uair.arizona.edu/index.php/radiocarbon/article/view/16458/16133">"Volume 4 – 1962"</a>. <i><a href="/wiki/Radiocarbon_(journal)" title="Radiocarbon (journal)">Radiocarbon</a></i>. <b>4</b> (1): i.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Radiocarbon&rft.atitle=Volume+4+%E2%80%93+1962&rft.volume=4&rft.issue=1&rft.pages=i&rft.date=1962&rft.aulast=Flint&rft.aufirst=Richard+Foster&rft.au=Deevey%2C+Edward+S&rft_id=https%3A%2F%2Fjournals.uair.arizona.edu%2Findex.php%2Fradiocarbon%2Farticle%2Fview%2F16458%2F16133&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFvan_der_Plicht2004" class="citation book cs1">van der Plicht, Johannes (January 2004). "Radiocarbon, the Calibration Curve and Scythian Chronology". <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110724164654/http://cio.eldoc.ub.rug.nl/FILES/root/2004/NATOSciIVvdPlicht/2004NATOSciIVvdPlicht.pdf"><i>NATO Science Series: IV: Earth and Environmental Sciences</i></a> <span class="cs1-format">(PDF)</span>. Vol. 42. Dordrecht: Springer Netherlands. pp. 45–61 (47). <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F1-4020-2656-0_5">10.1007/1-4020-2656-0_5</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1-4020-2655-3" title="Special:BookSources/978-1-4020-2655-3"><bdi>978-1-4020-2655-3</bdi></a>. Archived from <a rel="nofollow" class="external text" href="http://cio.eldoc.ub.rug.nl/FILES/root/2004/NATOSciIVvdPlicht/2004NATOSciIVvdPlicht.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 2011-07-24<span class="reference-accessdate">. Retrieved <span class="nowrap">8 August</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Radiocarbon%2C+the+Calibration+Curve+and+Scythian+Chronology&rft.btitle=NATO+Science+Series%3A+IV%3A+Earth+and+Environmental+Sciences&rft.place=Dordrecht&rft.pages=45-61+%2847%29&rft.pub=Springer+Netherlands&rft.date=2004-01&rft_id=info%3Adoi%2F10.1007%2F1-4020-2656-0_5&rft.isbn=978-1-4020-2655-3&rft.aulast=van+der+Plicht&rft.aufirst=Johannes&rft_id=http%3A%2F%2Fcio.eldoc.ub.rug.nl%2FFILES%2Froot%2F2004%2FNATOSciIVvdPlicht%2F2004NATOSciIVvdPlicht.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></span> </li> <li id="cite_note-Taylor-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-Taylor_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Taylor_3-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTaylor_RE1985" class="citation journal cs1">Taylor RE (1985). 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Retrieved <span class="nowrap">2020-01-09</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Smithsonian+Magazine&rft.atitle=Nuclear+Bombs+Made+It+Possible+to+Carbon+Date+Human+Tissue&rft.date=2013-02-19&rft_id=https%3A%2F%2Fwww.smithsonianmag.com%2Fsmart-news%2Fnuclear-bombs-made-it-possible-to-carbon-date-human-tissue-20074710%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></span> </li> <li id="cite_note-Archaeology-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-Archaeology_19-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGreene2002" class="citation book cs1"><a href="/wiki/Kevin_Greene_(archaeologist)" title="Kevin Greene (archaeologist)">Greene, Kevin</a> (2002). <i>Archaeology: An Introduction</i>. Philadelphia: University of Pennsylvania Press. pp. 165–167. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-8122-1828-0" title="Special:BookSources/0-8122-1828-0"><bdi>0-8122-1828-0</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Archaeology%3A+An+Introduction&rft.place=Philadelphia&rft.pages=165-167&rft.pub=University+of+Pennsylvania+Press&rft.date=2002&rft.isbn=0-8122-1828-0&rft.aulast=Greene&rft.aufirst=Kevin&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></span> </li> <li id="cite_note-jqs-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-jqs_20-0">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWalkerJonsenRasmussenPopp2009" class="citation journal cs1">Walker, Mike; Jonsen, Sigfus; Rasmussen, Sune Olander; Popp, Trevor; Steffensen, Jørgen-Peder; Gibbard, Phil; Hoek, Wim; Lowe, John; Andrews, John; <a href="/wiki/Svante_Bj%C3%B6rck" title="Svante Björck">Björck, Svante</a>; Cwynar, Les C.; Hughen, Konrad; Kershaw, Peter; Kromer, Bernd; Litt, Thomas; Lowe, David J.; Nakagawa, Takeshi; Newnham, Rewi; Schwander, Jacob (2009). <a rel="nofollow" class="external text" href="http://www.stratigraphy.org/GSSP/Holocene.pdf">"Formal definition and dating of the GSSP (Global Stratotype Section and Point) for the base of the Holocene using the Greenland NGRIP ice core, and selected auxiliary records"</a> <span class="cs1-format">(PDF)</span>. <i>Journal of Quaternary Science</i>. <b>24</b> (1): 3–17. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2009JQS....24....3W">2009JQS....24....3W</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1002%2Fjqs.1227">10.1002/jqs.1227</a></span>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20131104131948/http://www.stratigraphy.org/GSSP/Holocene.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2013-11-04.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+Quaternary+Science&rft.atitle=Formal+definition+and+dating+of+the+GSSP+%28Global+Stratotype+Section+and+Point%29+for+the+base+of+the+Holocene+using+the+Greenland+NGRIP+ice+core%2C+and+selected+auxiliary+records&rft.volume=24&rft.issue=1&rft.pages=3-17&rft.date=2009&rft_id=info%3Adoi%2F10.1002%2Fjqs.1227&rft_id=info%3Abibcode%2F2009JQS....24....3W&rft.aulast=Walker&rft.aufirst=Mike&rft.au=Jonsen%2C+Sigfus&rft.au=Rasmussen%2C+Sune+Olander&rft.au=Popp%2C+Trevor&rft.au=Steffensen%2C+J%C3%B8rgen-Peder&rft.au=Gibbard%2C+Phil&rft.au=Hoek%2C+Wim&rft.au=Lowe%2C+John&rft.au=Andrews%2C+John&rft.au=Bj%C3%B6rck%2C+Svante&rft.au=Cwynar%2C+Les+C.&rft.au=Hughen%2C+Konrad&rft.au=Kershaw%2C+Peter&rft.au=Kromer%2C+Bernd&rft.au=Litt%2C+Thomas&rft.au=Lowe%2C+David+J.&rft.au=Nakagawa%2C+Takeshi&rft.au=Newnham%2C+Rewi&rft.au=Schwander%2C+Jacob&rft_id=http%3A%2F%2Fwww.stratigraphy.org%2FGSSP%2FHolocene.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></span> </li> <li id="cite_note-Dershowitz-21"><span class="mw-cite-backlink">^ <a href="#cite_ref-Dershowitz_21-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Dershowitz_21-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDershowitzReingold2008" class="citation book cs1"><a href="/wiki/Nachum_Dershowitz" title="Nachum Dershowitz">Dershowitz, Nachum</a>; <a href="/wiki/Edward_M._Reingold" class="mw-redirect" title="Edward M. Reingold">Reingold, Edward M.</a> (2008). <a href="/wiki/Calendrical_Calculations" title="Calendrical Calculations"><i>Calendrical Calculations</i></a> (3rd ed.). Cambridge University Press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-521-70238-6" title="Special:BookSources/978-0-521-70238-6"><bdi>978-0-521-70238-6</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Calendrical+Calculations&rft.edition=3rd&rft.pub=Cambridge+University+Press&rft.date=2008&rft.isbn=978-0-521-70238-6&rft.aulast=Dershowitz&rft.aufirst=Nachum&rft.au=Reingold%2C+Edward+M.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></span> </li> <li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.stratigraphy.org/index.php/ics-news-and-meetings/120-ics-chart-containing-the-quaternary-gssps-and-new-stages-v-2018-07-is-now-released">"ICS chart containing the Quaternary and Cambrian GSSPs and new stages (v 2018/07) is now released!"</a><span class="reference-accessdate">. Retrieved <span class="nowrap">February 6,</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=ICS+chart+containing+the+Quaternary+and+Cambrian+GSSPs+and+new+stages+%28v+2018%2F07%29+is+now+released%21&rft_id=http%3A%2F%2Fwww.stratigraphy.org%2Findex.php%2Fics-news-and-meetings%2F120-ics-chart-containing-the-quaternary-gssps-and-new-stages-v-2018-07-is-now-released&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></span> </li> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFConners2018" class="citation web cs1">Conners, Deanna (September 18, 2018). <a rel="nofollow" class="external text" href="https://earthsky.org/earth/new-name-present-times-era-meghalayan">"Welcome to the Meghalayan age"</a><span class="reference-accessdate">. Retrieved <span class="nowrap">February 6,</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Welcome+to+the+Meghalayan+age&rft.date=2018-09-18&rft.aulast=Conners&rft.aufirst=Deanna&rft_id=https%3A%2F%2Fearthsky.org%2Fearth%2Fnew-name-present-times-era-meghalayan&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCurrie_Lloyd_A2004" class="citation journal cs1">Currie Lloyd A (2004). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20101206195414/http://nvl.nist.gov/pub/nistpubs/jres/109/2/j92cur.pdf">"The Remarkable Metrological History of Radiocarbon Dating [II]"</a> <span class="cs1-format">(PDF)</span>. <i>Journal of Research of the National Institute of Standards and Technology</i>. <b>109</b> (2): 185–217. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.6028%2Fjres.109.013">10.6028/jres.109.013</a>. <a href="/wiki/PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4853109">4853109</a></span>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/27366605">27366605</a>. Archived from <a rel="nofollow" class="external text" href="http://nvl.nist.gov/pub/nistpubs/jres/109/2/j92cur.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 2010-12-06<span class="reference-accessdate">. Retrieved <span class="nowrap">2018-06-24</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+Research+of+the+National+Institute+of+Standards+and+Technology&rft.atitle=The+Remarkable+Metrological+History+of+Radiocarbon+Dating+%26%2391%3BII%26%2393%3B&rft.volume=109&rft.issue=2&rft.pages=185-217&rft.date=2004&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC4853109%23id-name%3DPMC&rft_id=info%3Apmid%2F27366605&rft_id=info%3Adoi%2F10.6028%2Fjres.109.013&rft.au=Currie+Lloyd+A&rft_id=http%3A%2F%2Fnvl.nist.gov%2Fpub%2Fnistpubs%2Fjres%2F109%2F2%2Fj92cur.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></span> </li> </ol></div></div> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(7)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Sources">Sources</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Before_Present&action=edit&section=8" title="Edit section: Sources" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-7 collapsible-block" id="mf-section-7"> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="Aitken1990" class="citation book cs1">Aitken, M.J. (1990). <i>Science-based Dating in Archaeology</i>. London: Longman. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-582-49309-4" title="Special:BookSources/978-0-582-49309-4"><bdi>978-0-582-49309-4</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Science-based+Dating+in+Archaeology&rft.place=London&rft.pub=Longman&rft.date=1990&rft.isbn=978-0-582-49309-4&rft.aulast=Aitken&rft.aufirst=M.J.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABefore+Present" class="Z3988"></span></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output 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id="page-secondary-actions"> </div> </main> <footer class="mw-footer minerva-footer" role="contentinfo"> <a class="last-modified-bar" href="/w/index.php?title=Before_Present&action=history"> <div class="post-content last-modified-bar__content"> <span class="minerva-icon minerva-icon-size-medium minerva-icon--modified-history"></span> <span class="last-modified-bar__text modified-enhancement" data-user-name="GoingBatty" data-user-gender="male" data-timestamp="1732487436"> <span>Last edited on 24 November 2024, at 22:30</span> </span> <span class="minerva-icon minerva-icon-size-small minerva-icon--expand"></span> </div> </a> <div class="post-content footer-content"> <div id='mw-data-after-content'> <div class="read-more-container"></div> </div> <div id="p-lang"> <h4>Languages</h4> <section> <ul id="p-variants" class="minerva-languages"></ul> <ul class="minerva-languages"><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%82%D8%A8%D9%84_%D8%A7%D9%84%D8%AD%D8%A7%D8%B6%D8%B1" title="قبل الحاضر – Arabic" lang="ar" hreflang="ar" data-title="قبل الحاضر" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Enantes_del_presente" title="Enantes del presente – Asturian" lang="ast" hreflang="ast" data-title="Enantes del presente" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%AC%E0%A6%B0%E0%A7%8D%E0%A6%A4%E0%A6%AE%E0%A6%BE%E0%A6%A8_%E0%A6%AA%E0%A7%82%E0%A6%B0%E0%A7%8D%E0%A6%AC" title="বর্তমান পূর্ব – Bangla" lang="bn" hreflang="bn" data-title="বর্তমান পূর্ব" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%94%D0%B0_%D0%BD%D0%B0%D1%88%D1%8B%D1%85_%D0%B4%D0%B7%D1%91%D0%BD" title="Да нашых дзён – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Да нашых дзён" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/BP_(escala_de_temps)" title="BP (escala de temps) – Catalan" lang="ca" hreflang="ca" data-title="BP (escala de temps)" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/B._P." title="B. P. – Czech" lang="cs" hreflang="cs" data-title="B. P." data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/CP" title="CP – Welsh" lang="cy" hreflang="cy" data-title="CP" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Before_Present" title="Before Present – German" lang="de" hreflang="de" data-title="Before Present" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Before_Present" title="Before Present – Estonian" lang="et" hreflang="et" data-title="Before Present" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Antes_del_presente" title="Antes del presente – Spanish" lang="es" hreflang="es" data-title="Antes del presente" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Before_Present" title="Before Present – Basque" lang="eu" hreflang="eu" data-title="Before Present" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%BE%DB%8C%D8%B4_%D8%A7%D8%B2_%D8%A7%D9%85%D8%B1%D9%88%D8%B2" title="پیش از امروز – Persian" lang="fa" hreflang="fa" data-title="پیش از امروز" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Avant_le_pr%C3%A9sent" title="Avant le présent – French" lang="fr" hreflang="fr" data-title="Avant le présent" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/BP_(%EA%B3%A0%EA%B3%A0%ED%95%99)" title="BP (고고학) – Korean" lang="ko" hreflang="ko" data-title="BP (고고학)" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/BP_(%D5%A9%D5%BE%D5%A1%D5%A3%D6%80%D5%B8%D6%82%D5%B4)" title="BP (թվագրում) – Armenian" lang="hy" hreflang="hy" data-title="BP (թվագրում)" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/BP" title="BP – Croatian" lang="hr" hreflang="hr" data-title="BP" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Sebelum_Sekarang" title="Sebelum Sekarang – Indonesian" lang="id" hreflang="id" data-title="Sebelum Sekarang" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Before_Present" title="Before Present – Italian" lang="it" hreflang="it" data-title="Before Present" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%9C%D7%A4%D7%A0%D7%99_%D7%96%D7%9E%D7%A0%D7%A0%D7%95" title="לפני זמננו – Hebrew" lang="he" hreflang="he" data-title="לפני זמננו" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Ante_praesentem" title="Ante praesentem – Latin" lang="la" hreflang="la" data-title="Ante praesentem" data-language-autonym="Latina" data-language-local-name="Latin" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Pirms_m%C5%ABsdien%C4%81m" title="Pirms mūsdienām – Latvian" lang="lv" hreflang="lv" data-title="Pirms mūsdienām" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Jelen_el%C5%91tti_%C3%A9vek" title="Jelen előtti évek – Hungarian" lang="hu" hreflang="hu" data-title="Jelen előtti évek" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%9F%D1%80%D0%B5%D0%B4_%D1%81%D0%B5%D0%B3%D0%B0%D1%88%D0%BD%D0%BE%D1%81%D1%82%D0%B0" title="Пред сегашноста – Macedonian" lang="mk" hreflang="mk" data-title="Пред сегашноста" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Sebelum_Kini" title="Sebelum Kini – Malay" lang="ms" hreflang="ms" data-title="Sebelum Kini" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Before_Present" title="Before Present – Dutch" lang="nl" hreflang="nl" data-title="Before Present" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-nds-nl mw-list-item"><a href="https://nds-nl.wikipedia.org/wiki/Before_Present" title="Before Present – Low Saxon" lang="nds-NL" hreflang="nds-NL" data-title="Before Present" data-language-autonym="Nedersaksies" data-language-local-name="Low Saxon" class="interlanguage-link-target"><span>Nedersaksies</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/BP_(%E5%B9%B4%E4%BB%A3%E6%B8%AC%E5%AE%9A)" title="BP (年代測定) – Japanese" lang="ja" hreflang="ja" data-title="BP (年代測定)" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Before_Present" title="Before Present – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Before Present" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Before_present" title="Before present – Polish" lang="pl" hreflang="pl" data-title="Before present" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Antes_do_presente" title="Antes do presente – Portuguese" lang="pt" hreflang="pt" data-title="Antes do presente" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%94%D0%BE_%D0%BD%D0%B0%D1%81%D1%82%D0%BE%D1%8F%D1%89%D0%B5%D0%B3%D0%BE_%D0%B2%D1%80%D0%B5%D0%BC%D0%B5%D0%BD%D0%B8" title="До настоящего времени – Russian" lang="ru" hreflang="ru" data-title="До настоящего времени" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/BP_(%C4%8Das)" title="BP (čas) – Slovak" lang="sk" hreflang="sk" data-title="BP (čas)" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D9%BE%DB%8E%D8%B4_%D8%A6%DB%8E%D8%B3%D8%AA%D8%A7" title="پێش ئێستا – Central Kurdish" lang="ckb" hreflang="ckb" data-title="پێش ئێستا" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9F%D1%80%D0%B8%D1%98%D0%B5_%D1%81%D0%B0%D0%B4%D0%B0%D1%88%D1%9A%D0%BE%D1%81%D1%82%D0%B8" title="Прије садашњости – Serbian" lang="sr" hreflang="sr" data-title="Прије садашњости" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/BP_(ajanlasku)" title="BP (ajanlasku) – Finnish" lang="fi" hreflang="fi" data-title="BP (ajanlasku)" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/B.P." title="B.P. – Swedish" lang="sv" hreflang="sv" data-title="B.P." data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%A8%E0%AE%BF%E0%AE%95%E0%AE%B4%E0%AF%8D%E0%AE%95%E0%AE%BE%E0%AE%B2%E0%AE%A4%E0%AF%8D%E0%AE%A4%E0%AE%BF%E0%AE%B1%E0%AF%8D%E0%AE%95%E0%AF%81_%E0%AE%AE%E0%AF%81%E0%AE%A9%E0%AF%8D" title="நிகழ்காலத்திற்கு முன் – Tamil" lang="ta" hreflang="ta" data-title="நிகழ்காலத்திற்கு முன்" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-tt mw-list-item"><a href="https://tt.wikipedia.org/wiki/%D0%91%D2%AF%D0%B3%D0%B5%D0%BD%D0%B3%D3%99%D1%87%D3%99" title="Бүгенгәчә – Tatar" lang="tt" hreflang="tt" data-title="Бүгенгәчә" data-language-autonym="Татарча / tatarça" data-language-local-name="Tatar" class="interlanguage-link-target"><span>Татарча / tatarça</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/G%C3%BCn%C3%BCm%C3%BCzden_%C3%B6nce" title="Günümüzden önce – Turkish" lang="tr" hreflang="tr" data-title="Günümüzden önce" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%A0%D0%BE%D0%BA%D1%96%D0%B2_%D1%82%D0%BE%D0%BC%D1%83" title="Років тому – Ukrainian" lang="uk" hreflang="uk" data-title="Років тому" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%D9%82%D8%A8%D9%84_%D8%AD%D8%A7%D8%B6%D8%B1" title="قبل حاضر – Urdu" lang="ur" hreflang="ur" data-title="قبل حاضر" data-language-autonym="اردو" data-language-local-name="Urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E8%B7%9D%E4%BB%8A" title="距今 – Chinese" lang="zh" hreflang="zh" data-title="距今" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li></ul> </section> </div> <div class="minerva-footer-logo"><img src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" alt="Wikipedia" width="120" height="18" style="width: 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