1. Yahoo News: “Humans Are Still Evolving, Study Says

Big deal over small, arguably irrelevant changes

Among the 30 families who settled on the isolated French Canadian island Ile aux Coudres, church records reveal that, from 1799 to 1940, mothers gradually began having children at younger ages. The average age of initial childbearing dropped from 26 to 22. Geneticist Emmanuel Milot contends that this younger onset of fertility represents human evolution by natural selection.

“It is often claimed that modern humans have stopped evolving because cultural and technological advancements have annihilated natural selection,” wrote Milot’s team in their paper, “Evidence for evolution in response to natural selection in a contemporary human population.”1 “Our study supports the idea that humans are still evolving. It also demonstrates that microevolution is detectable over just a few generations.”2

“We think, traditionally, that the changes in human population are mainly cultural, which is why a non-genetic hypothesis is given priority over a genetic or evolutionary hypothesis, whether or not there is data to support that,” Milot explained. “We have data that we analyzed from the genetic and nongenetic point of view, and we find that the genetic factors are stronger.” The team attributes 30–50 percent of the change to inherited genetic differences and 50–70 percent to cultural factors. But Milot contends, “Culture shapes the selection pressures. . . . The cultural context was favoring the selection of some genes.”2

The study did not identify any actual genes involved in this change. Milot’s team suggested that possible inherited factors could include fertility, age at puberty, or personality traits. But they add that cultural factors like economic prosperity could act as the “selection pressure” favoring earlier childbearing and consequently larger families.

To assess the significance of these results, we need to consider the validity of Milot’s conclusions as well as his study’s implications. First of all, Milot’s contention that natural selection produced 30-50% of the difference seems to ignore other more likely factors. When phenotypic changes occur within small populations, genetic drift or founder effect is often the cause.

Genetic drift is the result of the simple probability that in each generation some individuals by chance leave behind more descendants than others. Those individuals’ genes, therefore, are more highly represented in the later populations without any regard to fitness for survival. Founder effect is the result of a genetic bottleneck, such as occurs when a small portion of a population is segregated and then reproduces with decreased genetic variability. Both genetic drift and founder effect are magnified in small populations. Milot seemed to acknowledge the possibility of the founder effect and proposed that natural selection was superimposed on it. He said that in “a newly founded population” perhaps “it was not disadvantageous to have big families” owing to improved economic resources.

Of greater significance than whether or not natural selection, genetic drift, or founder effect influenced the fertility of this isolated group is the assertion that “humans are still evolving.” Common sense creationists have never disputed the role of these factors in altering the characteristics of a population of any kind of creature. The key distinction is whether or not Milot’s discovery suggests that human evolution has ever occurred, much less is “still” occurring.

As Milot says, his study concerns “microevolution.” Microevolution refers only to changes within a created kind. Again, creationists have never disputed the occurrence of these sorts of changes.3 Evolutionists contend, however, that given enough time microevolution will lead to macroevolution of new kinds of organisms. Proverbially, they say that “macroevolution is just microevolution writ large, or that the process we see and study as the cause of microevolution will, given sufficient time, also cause everything we attribute to macroevolution.”4 However, so-called macroevolution would require the acquisition of new genetic information. Microevolution only involves the loss or reshuffling of existing genetic information within a created kind. Therefore, the two are changes of wholly different types and are not logically connected. (We prefer avoiding either term to avoid confusion.)

So, are “humans still evolving”? Well, have genetic characteristics of this population changed over time? Possibly. Have the changes observed here been influenced by natural selection? Perhaps. But does this study offer any evidence that humans are gradually evolving into some sort of higher life form or by implication evolved from some lower life form? Absolutely not.

As we learn in the Bible, God created all kinds of organisms during Creation week and designed them to reproduce after their kinds. They only vary within their created kinds. On the sixth day, God created Adam and Eve, and He likewise provided them with the capacity to produce humans with many genetic variations. These variations have naturally interacted with culture and with selection pressures over time. But the first man and woman were not lower forms of life. Furthermore, any future destiny of human beings will not involve evolution into higher life forms but only the changes that God in His grace will perform at “the times of restoration of all things” (Acts 3:21). The Bible tells us the truth about the origins of humanity and what we can expect in the future.

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2. U.C.–Berkeley: “Bees outpace orchids in evolution

Orchids pack their pollen on perfume-seeking bees.

Many species of orchids depend on specific species of male bees for pollination, and the corresponding bees likewise depend on orchids for fragrances to facilitate their mating practices. The orchid attracts the bee and attaches a mass of sticky pollen to it. The blob of pollen is later scraped off in an orchid of the same type. How did such mutualistic associations develop?

Evolutionists have assumed these organisms co-evolved “nearly simultaneously”5 in a back-and-forth stepwise fashion. Nevertheless, “the evolutionary processes that gave rise to these associations remain poorly understood.”6

In an effort to sort out this “chicken-or-the-egg” mystery, a Berkeley research team led by Santiano Ramírez combined DNA-sequencing of many euglossine bee species and the pollen they carried with chemical analyses of orchid fragrances and the compounds collected by the bees. Ramírez was surprised to learn that the bees could obtain 90% of the chemicals they seek from sources such as tree resins, fungi, and rotting vegetation. Thus, the mutualistic dependence is quite one-sided. The orchids need the bees more than the bees need the orchids.

After comparing genomes and analyzing molecular clock calculations, the Berkeley team concluded that euglossine bee species diverged from their common ancestor 12 million years before euglossine-pollinated orchids diverged from theirs. Therefore, the researchers conclude that the orchid varieties that were able to produce those particular volatile chemical compounds already being sought by the bees had a reproductive advantage.7 Natural selection thus culminated in the mutualistic pairings we see. Ramírez said, “It appears that the male bees evolved a preference to collect these compounds from all kinds of sources, and the orchids converged on that chemical preference millions of years later. . . .The bees evolved much earlier and independently, while the orchids appear to have been catching up.”

The Berkeley study combines observational science with speculation. The genome analyses, the chemical analyses of the fragrances produced by orchids, and the chemical analyses of the chemicals sought by bees are solid observations. It does appear that the orchid-bee mutualism is a somewhat lop-sided dependence. The researchers reasonably suggest that orchids able to provide chemicals for which the bees already had a sensory bias6 possessed a reproductive advantage.

Since the genomes being compared were of the same kinds of organisms, the observed differences are variations within a created kind. However, the millions of years inferred from the data spring from unverifiable assumptions. Molecular clock calibration here depends on assumptions8 about mutation rates required for speciation and more assumptions about the dates of the fossil record.

These researchers themselves note, “Molecular clock estimates may suffer from biases due to incomplete lineage sampling, substitution rate heterogeneity, or sparse fossil data.”9 And what fossil data there is has been dated according to additional unverifiable assumptions about radiometric dating.10

The researchers note that the molecular clock data agrees with that of previous studies, but those studies suffered from the same “biases”; therefore, these studies should not be used to verify each other.

Biblically, we know that God made all kinds of plants on the third day of Creation week and flying insects on the fifth day. God created plants and animals to reproduce successfully, so we can conclude that He created some organisms capable of forming productive partnerships such as we see here. The genetic capacity to vary would enable some organisms to establish new mutualistic partnerships as conditions change. But we know that over time some organisms can fail to adapt and become extinct. (By the way, extinction is also explained in the Christian worldview: the Bible in Genesis 3 teaches that Adam’s sin brought death to animals—and humans—as God cursed all of creation.)

No evolution of new kinds of organisms is being discussed here but only the interaction and interdependence of variations within created kinds. The actual time of appearance of plants was just two days before the appearance of their insect pollinators, not 12 million years. And the intricate mechanisms by which an orchid packages and attaches its pollen packet to its bee smacks of “irreducible complexity” designed by our Creator. Biblical principles explain the origin of mutualism. Read more about it at God Created Cohorts and God Created Plant Pollinator Partners.

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3. Fox News: “Is Life on Other Planets Part of God’s Plan?

Did E. T. sin, and, if so, did Jesus die to save him/it?

The “100-Year Starship Symposium” met in Orlando for three days last week to discuss ideas related to interstellar travel. Speakers discussed topics ranging from physics to philosophy. Protestant philosophy professor Christian Weidemannof spoke at a panel discussion about the religious issues raised by the possibility of intelligent extraterrestrial life.

DARPA—the Defense Advanced Research Projects Agency—says it sponsored the symposium hoping “to inspire several generations to commit to the research and development of breakthrough technologies and cross-cutting innovation across myriad disciplines”11 to prepare for interstellar travel in the next 100 years. While DARPA and NASA ponder the question of how to best spend the $1 million allocated to the program, Christians are discussing whether interstellar seekers should expect to find any new life and new civilizations. And if so, how would those beings stand with God?

“Did Jesus die for Klingons too?” asked Weidemann, explaining the issue: “According to Christianity, an historic event some 2,000 years ago was supposed to save the whole of creation. You can grasp the conflict. . . . If there are extraterrestrial intelligent beings at all, it is safe to assume that most of them are sinners too. If so, did Jesus save them too? My position is no.”12

Christian apologist Lee Strobel in an interview with Fox News, disagreed, saying, “If there are other conscious, moral creatures on other planets, perhaps they would still be living in an innocent state.” He considers the possibility of extraterrestrial life highly improbable, though.

Answers in Genesis’ astrophysicist Jason Lisle, however, like Weidemann, says, “The discovery of intelligent life from other planets would be a challenge to the Christian worldview” adding that “no evidence of extraterrestrial intelligence has ever been detected.” Nevertheless, he says, “It was on Earth that God Himself became a human being -- not a Vulcan or Klingon.”

God created the entire universe. God’s Son Jesus Christ came to Earth as a human being, the “last Adam,” (I Corinthians 15:45-47) to die for all human beings who, like their real common ancestor—the first Adam—are sinners. We also know from God’s Word that the whole creation groans with corruption (Romans 8:21-22) under the curse of man’s sin. Thus the theological position of extraterrestrial intelligent life would cast aspersions on God’s character, as such beings would be reaping the guilty whirlwind of man’s sin without access to the grace of Christ.

Frankly, however, the issue of extraterrestrial life becomes somewhat moot if we consider the reason many people have for seriously thinking the sci-fi version of space is realistic. Despite the contention of some that God is great enough to have created many aliens on many worlds, we have no evidence either in God’s Word or in outer space that He did.

Furthermore, those who really expect to find E.T. often do so because they believe—contrary to God’s Word—that life evolved here from random chemical interactions and that in a huge universe it must have done so many times. In fact, constant exposure to the notion that the universe is billions of years old puts many in the mindset to consider intelligent aliens a reality.

Scripture teaches that life did not randomly evolve but was created by God over the course of one week. God spent the Creation Week preparing a place for Adam and Eve and created them in His image. Despite the fun of sci-fi, neither mankind nor the world evolved, so there is no reason to believe life evolved elsewhere either.

Furthermore, like our ancestor Adam we all have a sinful nature and need the salvation God offers. We are sufficiently special to our Creator that He sent His Son to earth to seek and to save lost human beings from the eternal consequences of sin. (Luke 19:10) Read more about it at Good News.

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4. PhysOrg: “Invasion of genomic parasites triggered modern mammalian pregnancy

Prefabricated package of genes prompts placental development.

Placental mammals and marsupial mammals are believed by evolutionists to have diverged from a common ancestor more than 100 million years ago. Now a Yale research team has unveiled the essential genetic difference that enables placental mammals to nurture their young in utero.

They discovered a 1532 gene unit13 regulated by a transposon. Transposons are bits of so-called “junk DNA” which can appear at various places in the genome and sometimes function in a regulatory capacity. Transposons have been likened to prefabricated cut-and-paste genetic parts. Because they resemble viruses, some evolutionists assume they entered the genome of some ancestor as a parasite and contributed either positively or negatively to the evolution of the organism.

“In the last two decades there have been dramatic changes in our understanding of how evolution works,” said Gunter Wagner, the senior author of the paper published in Nature Genetics. “We used to believe that changes only took place through small mutations in our DNA that accumulated over time. But in this case we found a huge cut-and-paste operation that altered wide areas of the genome to create large-scale morphological change.”

By comparing the genomes of marsupial opossums to the genomes of armadillos and humans—two placental mammals—the Yale team discovered the placental mammals each possessed a large block of genes that are only expressed in the uterine lining of placentals. About 13% of those genes are part of the non-coding transposon that regulates their expression.

“Transposons grow like parasites that have invaded the body, multiplying and taking up space in the genome,” said lead author Vincent J. Lynch, but this transposon activates the genes that enable the uterus to respond to hormonal signals and develop a placenta.

“These transposons are not genes that underwent small changes over long periods of time and eventually grew into their new role during pregnancy,” Lynch added. “They are more like prefabricated regulatory units that install themselves into a host genome, which then recycles them to carry out entirely new functions like facilitating maternal-fetal communication.” Thus, the researchers contend that “the evolution of pregnancy was associated with a large-scale rewiring of the gene regulatory network.”13

Evolutionists debate the origin of transposons. Such a transposon—if it were the evolutionary marvel so claimed—would be the agent of giant evolutionary leaps. Microorganisms are designed to horizontally transfer genomic islands of information, but such a process is not seen in mammals. Furthermore, when evolutionists make such a claim, they leave open a new question: namely, where did the information in the transposon come from?

What the research team has in fact uncovered is not the genomic parasite that gave placental mammals the ability to branch off on the phylogenetic tree but a genetic package designed by God to equip creatures He designed to be placental mammals to form placentas. And the presence of a similar chunk of 1532 genes in both humans and armadillos does not imply we share an evolutionary ancestor. It instead supports the biblical truth that we share a Common Designer who used the same package of gene regulators to enable those placental functions needed in both.

Read more about how “junk DNA” can be God’s tool at ‘Junk’ DNA: Evolutionary Discards or God’s Tools?.

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5. BBC: “Old fossils solve mystery of earliest bird extinction

Assorted archaic birds buried with dinosaurs up to the K-T boundary

Evolutionary paleontologists have long debated how and when archaic birds met their demise. Did they gradually die out during the Cretaceous Period? Or were they catastrophically wiped out by the meteoric mass extinction event that supposedly annihilated “non-avian” dinosaurs?

Analysis of fossilized bird bones from the uppermost Cretaceous layers has for the first time demonstrated a great deal of archaic bird diversity right up to within 300,000 years of the K-T boundary, by evolutionary reckoning. Evolutionists can now be confident that archaic birds went the way of the dinosaurs.

Archaic birds include Archeopteryx and a variety of other toothed birds. Their fossil record had been thought to end in the lower part of the Cretaceous. There is some fossil evidence of modern birds in the Cretaceous layer but a wider variety of them above the K-T (Cretaceous-Tertiary) boundary. Therefore, evolutionists maintain that the K-T boundary represents the time when modern birds evolved.

To resolve the gradual-versus-sudden extinction question, a team from Yale and Saskatchewan examined fossils from the only known locations where the geologic column contains lots of bird fossils in the uppermost part of the Cretaceous. A century’s worth of bird fossils from Hell Creek Formation (in Montana, North Dakota, and South Dakota), Wyoming’s Lance Formation, and Saskatchewan’s Frenchman Formation were sorted and analyzed. The team focused attention on the coracoid bone, a commonly preserved shoulder bone that tends to be fairly distinctive within species, thus eliminating the problem of counting some fossils twice.

The team identified 17 different species of birds. Of these, 7 were archaic birds of various sorts, including several waterfowl. These 7 archaic types have never been found above the K-T boundary. The researchers conclude that a diversity of archaic birds survived right up to the time of the meteoric impact that they believe doomed the dinosaurs and many other types of creatures to extinction.

Radiometric dating of these formations assigns them to the final 1.5 million years of the Cretaceous, and paleomagnetic dating narrows the dates to the final 300,000 years before the apparent mass extinction, by evolutionary reckoning. Molecular clock data has been “conflicting” due, according to the published study, to the lack of a well-dated fossil record.14 Here the research team is acknowledging that molecular clock calculations are wholly dependent on the dating of (and therefore on the assumptions made about) the fossil record.

Yet radiometric dating and paleomagnetic dating is replete with its own set of unverifiable assumptions. In particular, the Hell Creek Formation was re-dated in 2002. The radiometric dates were obtained by argon-argon dating. Argon-argon dating must always be calibrated according to a sample of a known date, but that “known” sample is itself dated by methods that suffer from assumptions about the starting ratios of the radioactive elements present, the constancy of the rate of decay, and the imperviousness of the sample to both contamination and material loss.10

Furthermore, the paleomagnetic dates of this inland continental formation are calibrated by deep sea cores from the South Atlantic. The authors of the re-dating study note that the precision of their results “assumes that sedimentation is constant for the time period being measured, and that all the cycles can be identified and counted.”15 The dates obtained for the strata from which these fossils came are as much a product of circular reasoning as the molecular clock calculations which depend on them.

But what about the archaic birds just below the K-T boundary? Did they get destroyed with the dinosaurs as a result of a meteorite? And why are some modern birds found in the Cretaceous layer? Given that there is no evidence for evolutionary progression from dinosaurs to archaic birds to modern birds, why do they all show up in the Cretaceous layer of western North America?

First of all, we know from the biblical record that we have not found such evolutionary progression because there was none. The Lord created all kinds of animals during Creation week. He created various kinds of birds, whether so-called “archaic” or “modern,” on day five. He created all kinds of dinosaurs on day six. And we have previously discussed16 the problems with the notion that a meteorite caused mass extinctions. (See Dinosaur Killer and News to Note, July 16, 2011 for a more volcanic explanation of how the global Flood caused the formation of the K-T boundary around 4,300 years ago, not 65 million!)

But how do biblical creationists account for the presence of the now-extinct “archaic” birds in the Cretaceous layer and the wide variety of “modern” birds above it? The layers in the geologic column represent not slow deposition and mass extinctions over millions of years, but rather the order of rapid burial during and soon after the Flood year.17

The lowest layers are dominated by marine creatures because those would have been the first buried by upheavals as the earth’s crust cracked as described in Genesis 7:11. The distribution of fossils in the higher layers would have depended in part upon animals’ abilities to flee the rising waters.

Birds capable of flight would have been able to flee for quite some time, accounting for their token presence in the Cretaceous and more common presence in layers above it. Many of the “archaic” birds are thought to be waterfowl. It may well be that they, like dinosaurs were native to ecosystems hit sooner by the Flood that those whose creatures are preserved in the higher layers.

Although we can be confident from the biblical record that all these archaic toothed bird kinds were represented on the Ark, they—like the dinosaurs—eventually became extinct some time after the Flood. But they did not become extinct at the K-T boundary. They just got buried in large numbers there. Read more about the biblical interpretation of the geologic column and its fossils in Chapter 31: Doesn’t the Order of Fossils in the Rock Record Favor Long Ages?

One final note: The researchers definitely made one “biblically accurate” interpretation. Despite the paucity of the Cretaceous bird fossil record in the rest of the world, they feel the fossil record is “consistent with the idea that the catastrophic extinction seen in North America was a global event.”18 Amen.

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And Don’t Miss . . .

  • An international team has assembled all known mammalian genomic data and with it has adjusted their phylogenetic tree. Their analysis uses a “relaxed molecular clock” which allows for different mutation rates in different kinds of animals. They of course calibrate their “time tree” with “age estimates for numerous fossil mammals.” Biologist Mark Springer explains, "We need to have calibrations to input into the analysis so that we know, for example, that elephants and their nearest relatives have been separate from each other since at least the end of the Paleocene -- more than 55 million years ago. We were able to put together a diverse assemblage of fossil calibrations from different parts of the mammalian tree, and we used it in conjunction with molecular information to assemble the most robust time tree based on sequenced data that has been developed to date." Geneticist William Murphy adds, "This study is the beginning of a larger plan to use large molecular data sets and sophisticated techniques for dating and estimating rates of diversification to resolve much larger portions of the mammalian tree, ultimately including all described species, as well as those that have gone recently extinct or for which only museum material may be available." The circular reasoning here should be very plain to see. Fossils are typically dated according to radiometric dating methods applied to the rock layers in which they are found. Those methods themselves are based on a number of unprovable assumptions.10 The molecular clock is calibrated on the basis of the fossil dates by assuming those creatures actually did evolve into each other—another unprovable assumption that assumes that genetic similarities prove common ancestry rather than revealing the common Designer. Then the molecular clock is used to deliver pronouncements about those same times. Despite offering the illusion of reliability with precise numerical data, evolutionary interpretations of the fossil record, molecular clocks, and the phylogenetic trees generated from them are no more reliable than broken clocks which are set to agree with each other.
  • There are remarkable niches for life on our planet, and that list of extreme habitats now includes the bottom of the Dead Sea. A diving team first found craters spewing fresh water into the 100-foot depths of the Dead Sea back in 2010 and is about to return for further exploration. Thick mats of bacteria have been found in craters 33 feet wide and 43 feet deep. These unusual bacteria thrive in the extremely salty water yet tolerate the fresh water that spews in periodically. “There are other hypersaline environments that are full of microbial life,” team member Ionescu noted, but tolerance for high levels of magnesium “in my opinion, makes our discovery even more surprising.” The upper parts of the craters contain bacteria that subsist on both sunlight and sulfides, and deeper are those that survive on sulfide alone. And no other kind of bacteria is known to be able to survive such shifts in salinity. God has equipped microorganisms with amazing adaptive abilities so that they can survive in changing conditions and continue to fulfill their niches in God’s Creation. These discoveries are a reminder that God’s original purpose in creating microorganisms probably included their role as an interface between the physical/chemical and living/biotic world.19 Literally and ironically, He even created a form of life that can survive in the depths of the inhospitable Dead Sea.
  • A fossilized troodontid theropod known as Talos sampsoni dug up in Utah has a fracture in the sickle-like claw of its second toe, leading to the suspicion that the animal held its toe off the ground as it walked. Earlier evidence from tracks supports this contention. Since the remainder of the skeleton is uninjured and the apparent bite-associated injury is partially healed, paleonotologists have come up with a number of behavioral conclusions that could possibly explain how the dinosaur used its claw. One interesting visual image is the idea that it may have wielded its talon like a sword. Dietary suggestions have also been made, proposing it must have been omnivorous to survive without hunting during the healing process. Study leader Lindsay Zanno says, “The more individual lines of evidence that we can add that can support the [weapon] hypothesis, the stronger it becomes.” But she admitted, “In the end we can never observe the behavior of this animal—it's always going to be controversial.” Thus we are reminded that a fossil does not demonstrate its behavior for us, and we should not accept dogmatic pronouncements about the diet and behavior of extinct creatures without a big grain of salt.

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  1. E. Milot et al. 2011. Proceedings of the National Academy of Sciences. 108 No. 40. Back
  2. www.wired.com/wiredscience/2011/10/recent-human-evolution Back (1) Back (2)
  3. News to Note, May 28, 2011 Back
  4. Toward an Accurate Model of Variation in DNA Back
  5. Ramírez et. al. 2011. “Asynchronous Diversification in a Specialized Plant-Pollinator Mutualism,” Science 333:1742 Back
  6. www.sciencemag.org/content/333/6050/1742.abstract Back (1) Back (2)
  7. www.sciencemag.org/content/333/6050/1742.full.pdf Back
  8. News to Note, June 25, 2011 Back
  9. Ramírez et. al. 2011. “Asynchronous Diversification in a Specialized Plant-Pollinator Mutualism,” Science 333:1743. Back
  10. Radiometric Dating: Back to Basics, Radiometric Dating: Problems with the Assumptions, Radiometric Dating: Making Sense of the Patterns Back (1) Back (2) Back (3)
  11. www.space.com/13135-100-year-starship-symposium-darpa-nasa.html Back
  12. www.space.com/13152-aliens-religion-impacts-extraterrestrial-christianity.html Back
  13. www.nature.com/ng/journal/vaop/ncurrent/full/ng.917.html Back (1) Back (2)
  14. N. Longrich et al., “Mass extinction of birds at the Cretaceous–Paleogene (K–Pg) boundary,” www.pnas.org/content/108/37/15253 Back
  15. Hicks et al. “Magnetostratigraphy and geochronology of the Hell Creek and basal Fort Union Formations of southwestern North Dakota and a recalibration of the age of the Cretaceous-Tertiary boundary.” GSA Special Paper 361:41. Back
  16. News to Note, October 1, 2011 Back
  17. Chapter 31: Doesn’t the Order of Fossils in the Rock Record Favor Long Ages? Back
  18. Longrich et al. “Mass extinction of birds at the Cretaceous–Paleogene (K–Pg) boundary,”www.pnas.org/content/108/37/15253 Back
  19. More Abundant than Stars Back