penguins after the flood

An Avian colonization of the southern hemisphere

Chad Arment (2022)

There are about twenty penguin species alive today (more or less, depending on which authorities you consult), comprising six genera within the family Spheniscidae (order Sphenisciformes). These include the great penguins (Aptenodytes), the little penguins (Eudyptula), the brush-tailed penguins (Pygoscelis), the banded penguins (Spheniscus), the crested penguins (Eudyptes), and the yellow-eyed penguin (Megadyptes). Twenty-one fossil genera are additionally placed in the Spheniscidae, while another seventeen fossil genera round out the order as basal or undetermined relations. Within phylogenetic studies, the extant penguins and their most recent common ancestor are referred to as ‘crown’ penguins, while the Sphenisciformes broadly envelops both ‘crown’ and fossil ‘stem’ penguins.

All modern penguins are flightless diving birds, with feathers and wings adapted to an aquatic lifestyle—penguin limb bones are much denser than typical avian bones, for example (Ksepka et al. 2015). Some penguins primarily feed on fish, some mainly eat krill, and others are generalists that include squid and other small sea life in their diet (Ksepka, Bertelli, and Giannini 2006).

A number of living and fossil penguins are (or were) circumpolar, adapted to living in Antarctic or sub-Antarctic waters, but there are (and were) other species that live in temperate and sub-tropical climates in South America and South Africa. Today, the Galapagos penguin lives in a tropical climate near the equator. As the northern tip of the island of Isabela crosses the equator, the Galapagos penguins living there are the only penguins living in the northern hemisphere.

Black-and-white plumage may aid in crypsis or in thermoregulation. (Cairns (1986) has a good discussion of black-and-white patterns found in many seabirds that dive for prey.) Flairs of yellow plumage pertain to mate selection in some species (Massaro, Davis, and Darby 2003; Jouventin et al. 2007). The orange spots on king and emperor penguin beaks are also highly UV reflective, aiding mate attraction (Jouventin et al. 2005; Jourventin, Couchoux, and Dobson 2009).

So where do penguins fit within a creationist model?

Is there a single penguin kind?

Within popular creationist traditions, the family level within Linnean taxonomy has become analogous by default with the biblical kind. With some terrestrial and flying creatures, that works (and is certainly more appropriate than genus or species), but it is likely inaccurate for other groups. It really depends on the amount of branching (diversification) within the kind after the Flood, and how quickly that branching took place. For a kind that exhibits little branching after the Flood, a family-level kind may be appropriate. The same would hold true for a kind that exhibits little branching in the immediate post-Flood world, but shows greater branching during the Ice Age. For kinds that immediately began branching in the post-Flood world, if those lineages continued to branch, it is possible that this would lead to a kind that includes multiple families. (For kinds that survived outside the Ark, like sharks or beetles, multiple pre-Flood branches may have survived the Flood intact, allowing greater post-Flood diversity within a kind.)

Within creationist studies, extant penguins within the family Spheniscidae are considered to belong to the same kind, due to statistical baraminology research and a strong cognitum (Wood 2008; Lightner 2013). This indicates that the Spheniscidae as a whole makes up a single kind. No studies so far have included the extinct fossil genera, but due to a consistent unique morphology connecting extant and fossil penguins, I believe a reasonable default position is that the order Sphenisciformes likely comprises a single kind.

Were there penguins on the Ark?

There is no clear-cut answer to this. If the penguin kind (in all that that entails) was always aquatic, then there may not have been penguins on the Ark. They may have survived the Flood through swimming, similar to sirenians, pinnipeds, and cetaceans.

Assume for a moment, though, that they were not included within aquatic creatures. Penguins are birds in modern taxonomy, but that does not mean they would have automatically been included in the biblical ‘flying creatures’ just because they have feathers; flightless terrestrial birds like ratites (ostriches, emus, etc.) would not have been, either. It depends on whether the Ark-period kind included species capable of flight.

If penguins were included on the Ark as flightless birds (so as ‘land animals’), they would have been considered unclean, so only a pair included. If the penguin kind was included on the Ark, but representatives within the kind were capable of flight, then they would have been considered (likely unclean) ‘flying creatures.’ There are two schools of thought within creation biology on how many pairs of flying creatures were on the Ark, based on varying interpretation of Genesis 7: some believe that only clean flying kinds were included with seven pairs each, while others believe all flying kinds were allowed seven pairs each.

Are there Fossil Pre-Flood Penguins?

As with most things that touch on the Flood/post-Flood boundary issue, there will be dissension regarding this question. As I believe the overall evidence clearly disconfirms a contiguous Late Cenozoic boundary, that leaves us with two main options: 1) a relatively contiguous boundary, mostly between the Cretaceous and Paleogene, and 2) a non-contiguous boundary that varies by location, but probably is Early Cenozoic in the main. So, are there any fossils of the penguin kind in the Flood record? I suspect not. The lowest stratigraphic fossil penguin is Waimanu, from lower Paleocene rocks in New Zealand. By the upper Paleocene strata, there are several additional genera in the same locality, and then we start to see an increase in dispersal and diversification. This could indicate that Waimanu was Ark-contemporary, whether it was on the Ark or not.

The Secular History of Penguins

Evolutionists believe that ‘stem’ penguins first evolved in the Cretaceous, but this is speculation from molecular studies rather than fossil finds (Jadwiszczak 2009), as the first Sphenisciformes appear in Paleocene sediments. Early immunological research suggested that penguins were related to loons, albatrosses, herons, and grebes (Ho et al. 1976), though a later phylogenetic study proposed storks as the closest penguin relation (Watanabe et al. 2006b). These phylogenetic relationships remain inconclusive, however, due to ‘discrepancies’ in the studies (Watanabe et al. 2006a).

George Gaylord Simpson speculated that penguin evolution likely proceeded via 1) an original flight-capable bird, 2) a small bird capable of both flight and wing-propelled diving, to 3) a bird becoming flightless but retaining its wing-propelled diving ability (Ksepka, Bertelli, and Giannini 2006). No fossils of such ‘proto-penguins’ are known, however. ‘Crown’ penguins are believed to have evolved in the Miocene in New Zealand and Australia (Subramanian et al. 2013; Vianna et al. 2020). It was likely only after the formation of permanent ice sheets in Antarctica that modern penguins (Aptenodytes and Pygoscelis) reinvaded that continent (Gavryushkina et al. 2017).

‘Crown’ penguins are best understood as “the product of a successful radiation of derived taxa [rather] than as an assemblage of survivors belonging to numerous lineages” (Ksepka, Bertelli, and Giannini 2006). (The lineage leading to Aptenodytes and Pygoscelis appears to have been an early split, though, from the rest of the ‘crown’ penguins (Degrange, Ksepka, and Tambussi 2018).)

A Creationist History of Penguins

The pattern of penguin adaptation in the fossil record best fits a Flood model with an ‘early’ boundary. Whether the earliest fossil penguins are pre-Flood or immediately post-Flood, there is a distinct increase in fine-tuning adaptation to a distinctly new and dramatically changing world up through to the modern ‘crown’ penguins. Ksepka, Bertelli, and Giannini (2006) note a number of morphological changes that occur within this lineage, including those to the flipper bones, the pectoral girdle, and the wing joints. The microstructure of ‘crown’ penguin flipper bones exhibits a more compact cortex compared to ‘stem’ penguins (Ksepka et al. 2015). Particularly interesting is that phalanges in a Paleocene Muriwaimanu wing are “strikingly similar to those of volant [flying] birds,” even though other bones show that it was not capable of flight (Mayr et al. 2020); functionally, however, “it must have used its wings in a different way than extant penguins.” Hind limb morphology of Paleocene species also differ from ‘crown’ penguins—possibly because they “may have played a greater role in underwater locomotion than they do in extant penguins, where the feet only function as rudders and do not produce thrust,” or because the earliest penguins hadn’t yet developed the upright walking posture (Mayr, et al. 2018).

By the Eocene, a giant fossil penguin’s (Inkayacu paracasensis) feathers showed undifferentiated primary wing feathers and broad body contour feathers, indicating rapid feather-shape adaptation to a prey-diving lifestyle (Clarke et al. 2010) within the kind. Melanosomes within Inkayacu feathers are more similar to other types of birds than to extant penguins, suggesting that the typical black-and-white coloration was a later adaptation. Beaks changed, shortening in length, deepening the mandible in planktonic feeders, housing a tongue covered in stiff, sharp lingual papillae to help force prey down the throat (Kobayashi et al. 1998). Short-beaked penguins first show up in the Miocene (Ksepka and Clarke 2010). Penguins developed an arterial adaptation to limit heat loss in cold water foraging by the Eocene, indicated by the presence of a humeral arterial sulcus, notably absent in basal penguins like the Paleocene Waimanu (Thomas, Ksepka, and Fordyce 2011). This pattern of adaptational advancement only makes sense with an early Flood boundary.

It should be noted that body size in early ‘stem’ penguins was highly variable, with very large and small species known. This size plasticity likely contributed to 10 different Eocene species coexisting on Seymour Island at the same time (Ksepka, Bertelli, and Giannini 2006). Today, sizes are much more stable, with only the king and emperor penguins distinctly taller than other extant species.

Regarding giant fossil penguins, there has been discussion regarding the validity of reports of these giants, as some early accounts exaggerated estimated heights. Accurate height estimates for even the emperor penguin, the largest living penguin, can be difficult to find, as secondary sources may report swimming posture lengths rather than true height. Ksepka et al. (2012) noted that measurements of wild emperor adults and museum specimens suggests that an average standing height of 1 meter is probably correct. They also stated, “We estimate that [the largest specimen of Kairuku grebneffi] stood about 1.28 m tall. . . . In underwater flight posture, Kairuku would have approached 1.5 m in length by virtue of the elongate projecting beak and trailing toes. . . . As Kairuku is one of the largest known penguins, we question published standing heights of >1.5 m for other penguins based on bones clearly smaller than those of Kairuku.” Mayr et al. (2017) recognized the issue with size estimates, but still suggested that their newly described Kumimanu biceae from Paleocene New Zealand had a body length of 1.77 m. So why don’t we have such large penguins today? The evidence suggests that the spread and diversification of marine mammals (pinnipeds and odontocetes) during the Oligocene period created too much pressure (whether competition or predation), so few giant penguins made it into the Miocene and none beyond (Mayr et al. 2017).

What Drove Penguin Diversification?

Several factors played their part. Early penguins species had strong, straight beaks, suggesting they were spear-fishers (Ksepka, Bertelli, and Giannini 2006; Chávez Hoffmeister 2020). Morphological diversification and dietary diversification likely went hand-in-hand.

Vianna et al. (2020) noted, “Our results suggest that adaptation across genes involved in multiple interconnected genetic pathways has increased the foraging success and survival of penguin species across diverse temperature and salinity gradients. Foraging success is associated with reproductive output and also with survival during long periods of fasting while caring for eggs and chicks. Collectively, such adaptations would have promoted the radiation of penguin species across the Southern Hemisphere.” Molecular adaptations likely influenced thermoregulation, osmoregulation, and diving capacity (oxygen storage) as new environmental climatic niches developed. This fits well with post-Flood biogeographic dispersal in the Southern Hemisphere, as penguins first spread out within a relatively stable warm period, then rapidly adapted to dramatic climate change.

Dispersal throughout the Southern Hemisphere was likely aided by the major ocean currents (Ksepka, Bertelli, and Giannini 2006), particularly the Antarctic Circumpolar Current (ACC) which grew steadily stronger after the opening of the Drake Passage (Park et al. 2016). Multiple, independent dispersal events occurred in both Australia and South Africa (Ksepka and Thomas 2012; Park et al. 2016). Cole et al. (2019) also pointed out, “one-third of all extant penguin species are endemic to geologically young islands,” suggesting that dispersal to subantarctic islands as they emerged in post-Flood waters was also a key driver of diversification. The founder effect, where a new population develops from only a few individuals, can contribute to speciation events within an open ecological niche (Templeton 2008).

Dispersal via the ACC may have been key for penguin speciation and long-term survival: we know that while penguins never invaded the Northern Hemisphere, another group of large, flightless seabirds, the Plotopteridae, occupied the North Pacific Ocean. They were pursuit divers like penguins. Species are known from the Eocene to Miocene, but they disappeared at that point. It's pure speculation, but perhaps a similar circumpolar current would have offered that kind more opportunities to disperse and adapt.

The Emperor Penguin: Antarctic Adaptation

While several penguin species live and breed in the Antarctic region, only the emperor penguin (Aptenodytes forsteri) has adapted to brooding and raising young during the harsh Antarctic winters (Le Maho 1977). It is likely that its adaptations to such a severe environment proceeded from a stage similar to that of its close relative the king penguin (A. patagonicus), which breeds on subantarctic islands around the southern pole. The emperor penguin has a mass ranging up to 45 kg, making it the heaviest species (king penguins only ranging to about 20 kg). It stands almost a meter high, a bit taller if walking with neck extended. They can dive more than 300 meters deep, and remain underwater for 20-30 minutes (Tamburrini et al. 1999). Molecular adaptation increased the emperor penguin’s ability to store oxygen, with Tamburrini et al. (1999) noting “the correlation between diving ability and high [myoglobin] concentration, among the highest measured in any species.” Emperor penguins primarily feed on fish, cephalopods, and crustaceans; males go on a fasting period of up to four months as they breed and then brood eggs (Robin et al. 1998).

During the Antarctic summer (January to March), emperor penguins feed and accumulate body fat (Le Maho 1977). In March, as sea ice begins to accumulate, mature penguins start traveling to nesting sites up to 75 miles inland, engage in courtship (which allows the partners to familiarize themselves with each other’s song), then mate. After the female lays a single egg, she carefully transfers it to the male’s feet (no nests are built), and if successful (the egg doesn’t break or end up sitting on the ice too long), the male will spend the next few months incubating it against his brood patch (a section of featherless skin allowing direct contact and warmth to the egg) while the female returns to the sea to feed. The female returns shortly after hatching, locates her mate and offspring (through a vocal search), and feeds the chick via regurgitation. (If the egg hatches before the female’s return, the male is able to offer the chick an esophageal secretion similar to pigeon milk (Le Maho 1977).) It is now the male’s turn to leave, feed, then return—the parents continue taking turns brooding and foraging. When the chicks are older, they will form a crèche with other chicks, huddling for warmth/protection and giving the parents more time to forage. (As would be expected, crèching behavior tends to be most advantageous for chicks that avoid the periphery (Le Bohec, Gauthier-Clerc, and Le Maho 2005).) When the chicks begin molting into juvenile plumage, the nesting colony treks back to the sea and the adults cease feeding their young.

Molting period for emperor penguins is November to January, and takes about a month. New feathers begin to push out, but are still attached to old feathers (Le Maho 1977). This allows the penguins to remain almost as insulated to the cold as when fully feathered. When the chicks fully have their juvenile plumage, they can survive the ocean waters. Mature penguins have a stiff outer layer of protective ‘contour feathers’ that cover a thick insulation layer of down (which includes both afterfeathers and plumules). There are over a dozen different types of feathers on an emperor penguin (Williams, Hagelin, and Kooyman 2015).

One of the reasons that the emperor penguin is able to survive and thrive in such an extremely cold environment as Antarctica is that, “Its large body mass, its shape, and its short extremities combine to give the emperor penguin the smallest relative surface area of any bird species” (Le Maho 1977).

Arid Adaptations

Of course, not all penguins live in the extreme cold. The African penguin, Spheniscus demersus, lives on the southwest coast of Africa, diving for prey in the cold ocean currents. Though often similar to a Mediterranean climate, this region can get very hot. African penguins exhibit behavioral adaptations for thermoregulation, including staying in the ocean during the heat of the day and returning to the colony in the evening and night (Frost, Siegfried, and Burger 1976). If they stay in the colony during the day (incubating eggs or guarding chicks), they may remain in their burrow-nests, or orient their dark backs to the sun (facilitating heat loss).

This adaptational balancing act (morphological adaptation to cold water diving, and behavioral adaptation to terrestrial heat) is shared by other penguins that live in subtropical to tropical environments. Boersma (1975) notes the Galapagos penguin (Spheniscus mendiculus) similarly regulate themselves. When in the cold water, Galapagos penguins can reduce their body temperatures slightly which lowers heat loss. They may also float with their dark backs exposed to the sun. Out of the water, their postures and flipper positions aid heat loss and minimize heat gain.

Penguin Feathers

Studies on South American Humboldt penguins (Spheniscus humboldti) revealed the birds’ feathers weren’t merely hydrophobic, but repelled supercool microdroplets, preventing ice adhesion (Wang et al. 2016). This anti-frosting ability developed from the barbed microstructure of the penguin feathers, which trapped micro-pockets of air, reducing surface contact with the microdroplets. Alizadeh-Birjandi et al. (2020) noted, in a study of both temperate and Antarctic species, three factors influencing strength of hydrophobicity and anti-icing: macroscopic structure of the feathers, nanoscale topography of the barbules, and the biochemistry of the penguin’s preening oil. Antarctic species showed greater overall adaptation to protective measures from the cold.

In extant penguins, the black-brown plumage is the result of large, ellipsoidal melanosomes not found in other birds (Clarke et al. 2010). As noted previously, the early fossil penguin Inkayacu appears to have had more colorful plumage. The little or blue penguins (Eudyptula minor) of New Zealand have feathers with a non-iridescent blue tint, deriving from β-keratin nanofiber structures in the barbs (D’Alba et al. 2011). As nanofibers are found in different feathers, regardless of color, it seems likely that blue feathers in penguins resulted from adaptation co-opting already present material for a different function (Kulp et al. 2018). The yellow pigment found in penguin species like king and macaroni penguins (termed ‘spheniscin,’ and found in plumage particularly important to mate selection) is distinctly different from feather pigments found in other birds (Thomas et al. 2013).


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