Sentences with phrase «age estimates»

Different studies often report substantial discrepancies between age estimates for groups of organisms implied by the fossil record and estimates generated by molecular clocks.

Radio - carbon dating is a method of obtaining age estimates on organic materials.

The case involved a mentally disabled woman, in her early 20's, with a cognitive / social / emotional clinical age estimated to be equivalent to that of an 8 year old.

By dating Lida Ajer sediment and formations, the scientists came up with age estimates for the human teeth and associated fossils of various rainforest animals excavated in the late 1800s, including orangutans.

Earlier this year, cosmologists realized that they could derive an independent age estimate by scrutinizing the cosmic microwave background, a primordial glow from the big bang that permeates space.

Still, it is «nearly impossible» to generate accurate age estimates of rock art based on uranium measures alone, researchers concluded in 2017 in Quaternary International.

To test their hypothesis, Rampino and Caldeira performed time - series analyses of impacts and extinctions using newly available data offering more accurate age estimates.

The comparison of the companion spectrum and photometry to model atmospheres indicates that the companion is an extremely dusty late L dwarf, with an intermediate gravity (log g 4.5 - 5.0) which is compatible with the independent age estimate of the system.

Sea - ice age estimates in spring, showing conditions during the last week of April in 2009 (upper image) and 2010 (lower image).

New age estimates for previously discovered fossils position Graecopithecus as potentially the earliest known hominid, the investigators suggest.

The previous age estimate...

[11] Asteroseismic analyses that incorporate the tight observational constraints on the stellar parameters for α Cen A and / or B have yielded age estimates of 7000484999999999999 ♠ 4.85 ± 0.5 Gyr, [7] 7000500000000000000 ♠ 5.0 ± 0.5 Gyr, [27] 5.2 — 7.1 Gyr, [28] 6.4 Gyr, [29] and 7000652000000000000 ♠ 6.52 ± 0.3 Gyr.

[30] Age estimates for stars A and B based on chromospheric activity (Calcium H & K emission) yield 4.4 — 6.5 Gyr, whereas gyrochronology yields 7000500000000000000 ♠ 5.0 ± 0.3 Gyr.

Rigor et al.; 4.2 million square kilometers; Statistical — age estimates In comparison to 2007 and 2008, there is much more first year (FY) ice in the Beaufort and Chukchi Seas in 2009, which we expect to precondition this area for a more extensive retreat than in 2007 and 2008.

Researchers have yet to test Lesedi fossils for DNA or to try to generate age estimates for the new finds.

Children in the three to six - year - old age range (Keep in mind that this is a rough age estimate.

Other researchers defend this technique as providing valuable minimum and maximum age estimates for rock art.

Analyses of thin mineral deposits partly covering painted cave areas provided minimum age estimates for the art, based on known decay rates of radioactive uranium in the rock.

Ötzi's bone and tissue have yielded comparable radiocarbon age estimates (SN: 5/27/17, p. 13).

Age estimates relied on measures of the decay of radioactive forms of argon and uranium in volcanic ash layers framing tool - bearing sediment.

In line with the new genetically derived age estimate for human origins, another team has proposed that approximately 300,000 - year - old fossils found in northwestern Africa belonged to H. sapiens (SN: 7/8/17, p. 6).

Moore and his colleagues base the youthful age estimate on the lack of craters in this scene.

An initial age estimate may come later this year if different dating techniques

The revised age — depth model reveals that the published age estimates based on some previously identified paleomagnetic events and optically stimulated luminescence dates from MAL05 - 1C are inaccurate for sediment older than ∼ 50 ka.

The YTT isochron provides an accurate and precise age estimate for the Lake Malawi paleoclimate record, which revises the chronology of past climatic events in East Africa.

However, uranium - thorium dating provides much more reliable results than methods such as radiocarbon dating, which can give false age estimates.

A Late Maastrichtian age estimate for the unit has been supported by both stable strontium isotope analyses [12] and ammonite biostratigraphy [13].

Note: The Heroic age estimate should be compared with the NASA Bootstrap modern climate rather than HadISST.

Radiocarbon dating is a method that provides objective age estimates for carbon - based materials that originated from living organisms.

And an article on Ad Age estimates, on average, UK & Australian subscribers listen to podcasts 5 — 6 hours per week.

Using loss rates producing plausible global lifetimes of SF6 (1000 to 3000 years), and tropospheric time variation matching observations, we find that age estimates inferred from SF6 mixing ratios may be significantly biased, and that this bias is increasing in time.

This example demonstrates some of the challenges in determining accurate age estimates and identifications of faint companions.

Although the new age estimates have wide margins of error, they help solidify our murky view of Denisovans and provide «really convincing evidence of multiple occupations of the cave,» says paleoanthropologist Fred Spoor of University College London.

The previous age estimate was based on a radiocarbon analysis of burned wood found in one of the animals» graves.

Although we can not be certain of the species that manufactured the artefacts, we note that the lithic assemblages were produced at a time corresponding with the origin of Homo sapiens in Africa based on mitochondrial DNA [40] and nuclear genomic [41] age estimates and fossil finds [42], [43].

Age estimates for the Misliya jaw jibe with an ancient DNA study published online July 4, 2017, in Nature Communications.

Based on my 401 (k) by age estimates, older - age savers (50 +) should be able to become 401 (k) millionaires around age 60 if they've been maxing out their 401 (k) and properly investing since the age of 23.

Because any age estimates using C - 14 prior to the Flood will give much older dates than the true age.

As a way of checking this age estimate, we can examine the oldest things we find in the universe to verify that they are 10 - 15 billion years old, but definitely not older.

Many dated deposits at the Spanish cave art sites contain rock particles from external sources that can throw off age estimates.

The team calculates an age of only 400 - 600 million years old, which agrees with the age estimated from its rotation period (a technique pioneered by CfA astronomer Soren Meibom).

NASA's Swift satellite picked up the short - lived burst Thursday — gamma - ray bursts usually last just minutes, even seconds — and a suite of follow - up observations of the explosion's afterglow at telescopes around the globe enabled an age estimate.