Information

Do omnivore mammals vary food preferences based on dietary needs?


I'm wandering if mammals that can eat many different kinds of food (omnivores) vary their preference for food not only based on the availability, but also based on dietary needs?

I'm looking at this site Food nutritional content and see that "not all foods are created equal" - the vitamin/mineral and amino acid contents can vary dramatically. Is there some part of an omnivore brain/digestive system that "monitors" the micronutrient density of digested food and adjusts food preferences towards foods that make the diet more complete?


For what concerns amino acids, mice rapidly reject meals that are not balanced in essential amino acids and continue to look for other kind of foods. This behavior is called aversion response and it is an adaptive phenomena that can be observed already 20 minutes after exposure to the unbalanced food. The mechanism involves brain sensing of uncharged tRNAs. The significance of the aversion response is to minimize depletion of essential amino acids that can not be directly synthethized but are required for protein synthesis. You can find good reviews in PubMed, for instance Gietzen et al. 2007, Annual Review of Nutrition, and Gietzen and Aya 2012, Molecular Neurobiology.


I found that there are seasonal rhythms in the nutrient intake: Seasonal rhythms of human nutrient intake and meal pattern

The article's abstract mentions carbohydrates, while I'm more interested in the micronutrients, like amino acids and vitamins/minerals.


Being an omnivore is actually quite odd

You are free to share this article under the Attribution 4.0 International license.

The first animal likely was a carnivore, new research finds. Humans, along with other omnivores, belong to a rare breed.

What an animal eats is a fundamental aspect of its biology, but surprisingly, the evolution of diet had not been studied across the animal kingdom until now.

The study is a deep dive into the evolutionary history of more than one million animal species going back 800 million years.

The study reveals several surprising key insights:

  • Many species living today that are carnivorous—those that eat other animals—can trace this diet back to a common ancestor more than 800 million years ago.
  • A plant-based, or herbivorous, diet is not the evolutionary driver for new species that scientists believed it to be.
  • Closely related animals tend to share the same dietary category—plant-eating, meat-eating, or both. This finding implies that switching between dietary lifestyles is not something that happens easily and often over the course of evolution.

The researchers scoured the literature for data on the dietary habits of more than a million animal species, from sponges to insects and spiders to house cats. They classified a species as carnivorous if it feeds on other animals, fungi, or protists (single-celled eukaryotic organisms, many of which live on bacteria). The researchers classified species as herbivorous if they depend on land plants, algae, or cyanobacteria for food, and omnivorous if they eat a mixture of carnivorous and herbivorous diets.

The scientists then mapped the vast dataset of animal species and their dietary preferences onto an evolutionary tree built from DNA-sequence data to untangle the evolutionary relationships between them.

Insects are a group in which feeding on plants increases rates of species proliferation, including among the butterflies and moths, which are almost all herbivorous. (Credit: Daniel Stolte/U. Arizona)

The whole animal kingdom’s menu

“Ours is the largest study conducted so far that examines the evolution of diet across the whole animal tree of life,” says lead author Cristian Román-Palacios, a doctoral student in the ecology and evolutionary biology department of at the University of Arizona. “We addressed three highly-debated and fundamental questions in evolutionary biology by analyzing a large-scale dataset using state-of-the-art methods.”

All species can be classified according to their evolutionary relationships, a concept that is known as phylogeny. Organisms are grouped into taxa, which define their interrelationships across several levels. For example, cats and dogs are different species but belong to the same order (carnivores). Similarly, horses and camels belong to a different order (ungulates.) Both orders, however, are part of the same class (mammals).

On the highest level, animals are classified in phyla. Examples of animal phyla are arthropods (insects, crustaceans, spiders, scorpions, and the like), mollusks (snails, clams, and squid fall into this phylum), and chordates, which include all animals with a backbone, including humans.

The survey suggests that across animals, carnivory is most common, including 63% of species. Another 32% are herbivorous, while humans belong to a small minority, just 3%, of omnivorous animals.

Unlike many of their land-dwelling kin, many so-called sea slugs such as this Spanish Shawl are carnivorous snails that prey on polyps, sponges or even each other. (Credit: Daniel Stolte/U. Arizona)

Tracing the evolution of eating meat

The researchers were surprised to find that many of today’s carnivorous species trace this diet back all the way to the base of the animal evolutionary tree, more than 800 million years, predating the oldest known fossils that paleontologists have been able to assign to animal origins with certainty.

“We don’t see that with herbivory,” says corresponding author John Wiens, a professor of ecology and evolutionary biology. “Herbivory seems to be much more recent, so in our evolutionary tree, it appears more frequently closer to the tips of the tree.”

So if the first animal was a carnivore, what did it prey on?

The authors suggest the answer might lie with protists, including choanoflagellates: tiny, single-celled organisms considered to be the closest living relatives of the animals. Living as plankton in marine and freshwater, choanoflagellates are vaguely reminiscent of miniature versions of the shuttlecock batted back and forth during a game of badminton.

A funnel-shaped collar of “hairs” surrounds a whip-like appendage called a flagellum whose rhythmic beating sucks a steady stream of water through the collar, filtering out bacteria and detritus that is then absorbed and digested. It is possible that the common ancestor of today’s animals was a creature very similar to a choanoflagellate.

“The ancient creature that is most closely related to all animals living today might have eaten bacteria and other protists rather than plants,” Wiens says.

Black vultures and Andean condors are carnivorous birds that specialize on consuming carrion. (Credit: Cristian Román-Palacios/University of Arizona)

Omnivores are super rare

Turning to a plant-based diet, on the other hand, happened much more frequently over the course of animal evolution.

Herbivory has traditionally been seen as a powerful catalyst for the origin of new species—an often-cited example is the insects, with an estimated 1.5 million described species the most diverse group among the arthropods. Many new species of flowering plants appeared during the Cretaceous period, about 130 million years ago, and the unprecedented diversity of flowers is widely thought to have coincided with an increase in insect species taking advantage of the newly available floral bounty.

“This tells us that what we see in insects doesn’t necessarily apply to other groups within the animal kingdom,” Wiens says. “Herbivory may go hand in hand with new species appearing in certain taxa, but it clearly is not a universal driver of new species.”

The study also revealed that omnivorous (“eating everything”) diets popped up rarely over the course of 800 million years of animal evolution, hinting at the possible explanation that evolution prefers specialists over generalists.

“You can be better at doing what you do if that is all you do,” Wiens says. “In terrestrial vertebrates, for example, eating a diet of leaves often requires highly modified teeth and a highly modified gut. The same goes for carnivory. Nature generally seems to avoid the dilemma of being a jack-of-all-trades and master of none, at least for diets.”

This need for specialization might explain why omnivores, such as humans, are rare, according to the authors. It might also explain why diets have often gone unchanged for so long.

“There is a big difference between eating leaves all the time and eating fruits every now and then,” Wiens says. “The specializations required to be an efficient herbivore or carnivore might explain why the two diets have been so conserved over hundreds of millions of years.”


Footnotes

© 2014 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0/, which permits unrestricted use, provided the original author and source are credited.

References

Palmqvist P, Gröcke DR, Arribas A& Fariña RA

. 2003 Paleoecological reconstruction of a lower Pleistocene large mammal community using biogeochemical (δ13C, δ15N, δ18O, Sr:Zn) and ecomorphological approaches . Paleobiology 29, 205–229. (doi:10.1666/0094-8373(2003)029<0205:PROALP>2.0.CO2). Crossref, ISI, Google Scholar

Evans AR, Wilson GP, Fortelius M& Jernvall J

. 2007 High-level similarity of dentitions in carnivorans and rodents . Nature 445, 78–81. (doi:10.1038/nature05433). Crossref, PubMed, ISI, Google Scholar

. 2010 Mammal teeth: origin, evolution, and diversity . Baltimore, MD : Johns Hopkins University Press . Google Scholar

Andrews P, Lord JM& Evans EMN

. 1979 Patterns of ecological diversity in fossil and modern mammalian faunas . Biol. J. Linnean Soc. 11, 177–205. (doi:10.1111/j.1095-8312.1979.tb00034.x). Crossref, Google Scholar

Fortelius M, Eronen J, Jernvall J, Liu L, Pushkina D, Rinne J, Tesakov A& Vislobokova I

. 2002 Fossil mammals resolve regional patterns of Eurasian climate change during 20 million years . Evol. Ecol. Res. 4, 1005–1016. Google Scholar

Liu L, Puolamäki K, Eronen JT, Ataabadi MM, Hernesniemi E& Fortelius M

. 2012 Dental functional traits of mammals resolve productivity in terrestrial ecosystems past and present . Proc. R. Soc. B 279, 2793–2799. (doi:10.1098/rspb.2012.0211). Link, ISI, Google Scholar

. 1977 Number of trophic levels in ecological communities . Nature 268, 329–331. (doi:10.1038/268329a0). Crossref, ISI, Google Scholar

. 1978 On feeding on more than one trophic level . Nature 275, 542–544. (doi:10.1038/275542a0). Crossref, ISI, Google Scholar

. 2003 Foraging adaptation and the relationship between food-web complexity and stability . Science 299, 1388–1391. (doi:10.1126/science.1079154). Crossref, PubMed, ISI, Google Scholar

Petchey OL, Beckerman AP, Riede JO& Warren PH

. 2008 Size, foraging, and food web structure . Proc. Natl Acad. Sci. USA 105, 4191–4196. (doi:10.1073/pnas.0710672105). Crossref, PubMed, ISI, Google Scholar

. 1981 The mammalian radiations: an analysis of trends in evolution, adaptation, and behavior . Chicago, IL : University of Chicago Press . Google Scholar

. 2005 Mammal species of the world: a taxonomic and geographic reference . Baltimore, MD : Johns Hopkins University Press . Google Scholar

. 2003 Mammal population regulation, keystone processes and ecosystem dynamics . Phil. Trans. R. Soc. Lond. B 358, 1729–1740. (doi:10.1098/rstb.2003.1359). Link, ISI, Google Scholar

. 2011 Ecology and evolution of mammalian biodiversity . Phil. Trans. R. Soc. B 366, 2451–2461. (doi:10.1098/rstb.2011.0090). Link, ISI, Google Scholar

. 1998 A new method of determining diets of rodents . J. Mammal. 79, 1198–1202. (doi:10.2307/1383011). Crossref, Google Scholar

. 1998 Using large mammal communities to examine ecological and taxonomic structure and predict vegetation in extant and extinct assemblages . Paleobiology 24, 384–408. Google Scholar

Mendoza M, Janis CM& Palmqvist P

. 2005 Ecological patterns in the trophic-size structure of large mammal communities: a ‘taxon-free’ characterization . Evol. Ecol. 7, 505–530. Google Scholar

. 1989 Food webs from the small to the large: the Robert H. MacArthur Award Lecture . Ecology 70, 1559–1589. (doi:10.2307/1938088). Crossref, Google Scholar

. 1979 The environment of Ramapithecus in Africa . Paleobiology 5, 22–30. Crossref, ISI, Google Scholar

McInnis ML, Vavra M& Krueger WC

. 1983 A comparison of four methods used to determine the diets of large herbivores . J. Range Manag. 36, 302–306. (doi:10.2307/3898474). Crossref, Google Scholar

. 2006 Determining the composition of herbivore diets in the Trans-Himalayan Rangelands: a comparison of field methods . Rangeland Ecol. Manag. 59, 512–518. (doi:10.2111/06-022R2.1). Crossref, Google Scholar

Balestrieri A, Remonti L& Prigioni C

. 2011 Assessing carnivore diet by faecal samples and stomach contents: a case study with Alpine red foxes . Central Eur. J. Biol. 6, 283–292. (doi:10.2478/s11535-010-0106-1). Google Scholar

. 1988 The reliability of fecal analysis as a method for determining the diet of insectivorous mammals . J. Mammal. 69, 108–113. (doi:10.2307/1381753). Crossref, Google Scholar

. 2000 How well can we simulate past climates? Evaluating the models using global palaeoenvironmental datasets . Q. Sci. Rev. 19, 321–346. (doi:10.1016/S0277-3791(99)00068-2). Crossref, Google Scholar

. 2000 Dietary preferences in extant African Bovidae . J. Mammal. 81, 490–511. (doi:10.1644/1545-1542(2000)081<0490:DPIEAB>2.0.CO2). Crossref, Google Scholar

. 1996 R: a language for data analysis and graphics . J. Comput. Graph. Stat. 5, 299–314. Google Scholar

. 1979 Algorithm AS 136: a k-means clustering algorithm . J. R. Stat. Soc. 28, 100. Google Scholar

. 1970 The Rodentia as omnivores . Q. Rev. Biol. 45, 351–372. (doi:10.1086/406647). Crossref, PubMed, ISI, Google Scholar

. 1991 Complex trophic interactions in deserts: an empirical critique of food-web theory . Am. Nat. 138, 123–155. (doi:10.1086/285208). Crossref, ISI, Google Scholar

. 2003 Understanding omnivory needs a behavioral perspective . Ecology 84, 2532–2537. (doi:10.1890/02-0397). Crossref, Google Scholar


Omnivorous species

General

Although cases exist of herbivores eating meat and carnivores eating plant matter, the classification "omnivore" refers to the adaptation and main food source of the species in general, so these exceptions do not make either individual animals or the species as a whole omnivorous. For the concept of "omnivore" to be regarded as a scientific classification, some clear set of measurable and relevant criteria would need to be considered to differentiate between an "omnivore" and other categories, e.g. faunivore, folivore, and scavenger. ⎱] Some researchers argue that evolution of any species from herbivory to carnivory or carnivory to herbivory would be rare except via an intermediate stage of omnivory. ⎲]

Omnivorous mammals

Various mammals are omnivorous in the wild, such as species of pigs, ⎳] badgers, bears, coatis, civets, hedgehogs, opossums, skunks, sloths, squirrels, ⎴] raccoons, chipmunks, ⎵] mice, ⎶] and rats. ⎷] The hominidae, including humans, chimpanzees, and orangutans, are also omnivores. Ε] ⎸] ⎹]

Most bear species are omnivores, ⎺] but individual diets can range from almost exclusively herbivorous (hypocarnivore) to almost exclusively carnivorous (hypercarnivore), depending on what food sources are available locally and seasonally. Polar bears are classified as carnivores, both taxonomically (they are in the order Carnivora), and behaviorally (they subsist on a largely carnivorous diet). Depending on the species of bear, there is generally a preference for one class of food, as plants and animals are digested differently. Wolf subspecies (including wolves, dogs, dingoes, and coyotes) eat some plant matter, but they have a general preference and are evolutionarily geared towards meat. ⎻] Also, the maned wolf is a canid whose diet is naturally 50% plant matter.

While most mammals may display "omnivorous" behavior patterns depending on conditions of supply, culture, season and so on, they will generally prefer a particular class of food, to which their digestive processes are adapted. Like most arboreal species, most squirrels are primarily granivores, subsisting on nuts and seeds. ⎼] But like virtually all mammals, squirrels avidly consume some animal food when it becomes available. For example, the American eastern gray squirrel has been introduced by humans to parts of Britain, continental Europe and South Africa. Where it flourishes, its effect on populations of nesting birds is often serious, largely because of consumption of eggs and nestlings. ⎽] ⎾]

Other species

Various birds are omnivorous, with diets varying from berries and nectar to insects, worms, fish, and small rodents. Examples include cassowaries, chickens, crows ⎿] and related corvids, kea, rallidae, and rheas. In addition, some lizards, turtles, fish (such as piranhas and catfish), and invertebrates are also omnivorous.

Quite often, mainly herbivorous creatures will eagerly eat small quantities of animal food when it becomes available. Although this is trivial most of the time, omnivorous or herbivorous birds, such as sparrows, often will feed their chicks insects while food is most needed for growth. ⏀] On close inspection it appears that nectar-feeding birds such as sunbirds rely on the ants and other insects that they find in flowers, not for a richer supply of protein, but for essential nutrients such as cobalt/vitamin b12 that are absent from nectar. Similarly, monkeys of many species eat maggoty fruit, sometimes in clear preference to sound fruit. ⏁] When to refer to such animals as omnivorous, or otherwise, is a question of context and emphasis, rather than of definition.


The Paleozoic diet: Why animals eat what they eat

Black vultures and Andean condors are carnivorous birds that specialize on consuming carrion. Credit: Cristian Román-Palacios/University of Arizona

In what is likely the first study to look at how dietary preferences evolved across the animal kingdom, UA researchers looked at more than a million species, going back 800 million years. The team reports several unexpected discoveries, including that the first animal likely was a carnivore and that humans, along with other omnivores, belong to a rare breed.

What an animal eats is a fundamental aspect of its biology, but surprisingly, the evolution of diet had not been studied across the animal kingdom until now. Scientists at the University of Arizona report several unexpected findings from taking a deep dive into the evolutionary history of more than one million animal species and going back 800 million years, when the first animals appeared on our planet.

The study, published in the journal Evolution Letters, revealed several surprising key insights:

  1. Many species living today that are carnivorous, meaning they eat other animals, can trace this diet back to a common ancestor more than 800 million years ago.
  2. A plant-based, or herbivorous, diet is not the evolutionary driver for new species that it was believed to be.
  3. Closely related animals tend to share the same dietary category—plant-eating, meat-eating, or both. This finding implies that switching between dietary lifestyles is not something that happens easily and often over the course of evolution.

Cristian Román-Palacios, Joshua Scholl and John Wiens, all with the Department of Ecology and Evolutionary Biology at the UA, scoured the literature for data on the dietary habits of more than a million animal species, from sponges to insects and spiders to housecats. A species was classified as carnivorous if it feeds on other animals, fungi or protists (single-celled eukaryotic organisms, many of which live on bacteria). Species were classified as herbivorous if they depend on land plants, algae or cyanobacteria for food, and omnivorous if they eat a mixture of carnivorous and herbivorous diets.

Insects are a group in which feeding on plants increases rates of species proliferation, including among the butterflies and moths, which are almost all herbivorous. Credit: Daniel Stolte/UANews

The scientists then mapped the vast dataset of animal species and their dietary preferences onto an evolutionary tree built from DNA-sequence data to untangle the evolutionary relationships between them.

"Ours is the largest study conducted so far that examines the evolution of diet across the whole animal tree of life," said doctoral student Román-Palacios, lead author of the paper. "We addressed three highly-debated and fundamental questions in evolutionary biology by analyzing a large-scale dataset using state-of-the-art methods."

All species can be classified according to their evolutionary relationships, a concept that is known as phylogeny. Organisms are grouped into taxa, which define their interrelationships across several levels. For example, cats and dogs are different species but belong to the same order (carnivores). Similarly, horses and camels belong to a different order (ungulates.) Both orders, however, are part of the same class (mammals). On the highest level, animals are classified in phyla. Examples of animal phyla are arthropods (insects, crustaceans, spiders, scorpions and the like), mollusks (snails, clams and squid fall into this phylum), and chordates, which include all animals with a backbone, including humans.

The survey suggests that across animals, carnivory is most common, including 63 percent of species. Another 32 percent are herbivorous, while humans belong to a small minority, just 3 percent, of omnivorous animals.

The researchers were surprised to find that many of today's carnivorous species trace this diet back all the way to the base of the animal evolutionary tree, more than 800 million years, predating the oldest known fossils that paleontologists have been able to assign to animal origins with certainty.

Unlike many of their land-dwelling kin, many so-called sea slugs such as this Spanish Shawl are carnivorous snails that prey on polyps, sponges or even each other. Credit: Daniel Stolte/UANews

"We don't see that with herbivory," said Wiens, professor of ecology and evolutionary biology and corresponding author of the study. "Herbivory seems to be much more recent, so in our evolutionary tree, it appears more frequently closer to the tips of the tree."

So if the first animal was a carnivore, what did it prey on?

The authors suggest the answer might lie with protists, including choanoflagellates: tiny, single-celled organisms considered to be the closest living relatives of the animals. Living as plankton in marine and freshwater, choanoflagellates are vaguely reminiscent of miniature versions of the shuttlecock batted back and forth during a game of badminton. A funnel-shaped collar of "hairs" surrounds a whip-like appendage called a flagellum whose rhythmic beating sucks a steady stream of water through the collar, filtering out bacteria and detritus that is then absorbed and digested. It is possible that the common ancestor of today's animals was a creature very similar to a choanoflagellate.

"The ancient creature that is most closely related to all animals living today might have eaten bacteria and other protists rather than plants," Wiens said.

Turning to a plant-based diet, on the other hand, happened much more frequently over the course of animal evolution.

Assassin flies (family Asilidae) are aggressive predators that feed on a variety of insects. Credit: Cristian Román-Palacios/University of Arizona

Herbivory has traditionally been seen as a powerful catalyst for the origin of new species—an often-cited example is the insects, with an estimated 1.5 million described species the most diverse group among the arthropods. Many new species of flowering plants appeared during the Cretaceous period, about 130 million years ago, and the unprecedented diversity of flowers is widely thought to have coincided with an increase in insect species taking advantage of the newly available floral bounty.

"This tells us that what we see in insects doesn't necessarily apply to other groups within the animal kingdom," Wiens said. "Herbivory may go hand in hand with new species appearing in certain taxa, but it clearly is not a universal driver of new species."

The study also revealed that omnivorous ("eating everything") diets popped up rarely over the course of 800 million years of animal evolution, hinting at the possible explanation that evolution prefers specialists over generalists.

"You can be better at doing what you do if that is all you do," Wiens said. "In terrestrial vertebrates, for example, eating a diet of leaves often requires highly modified teeth and a highly modified gut. The same goes for carnivory. Nature generally seems to avoid the dilemma of being a jack-of-all-trades and master of none, at least for diets."

This need for specialization might explain why omnivores, such as humans, are rare, according to the authors. It might also explain why diets have often gone unchanged for so long.

"There is a big difference between eating leaves all the time and eating fruits every now and then," Wiens said. "The specializations required to be an efficient herbivore or carnivore might explain why the two diets have been so conserved over hundreds of millions of years."


How Omnivorous Diets Change

Omnivorous bird species often change their diet seasonally for whatever food sources are most readily available. For many birds, this means eating insects in the spring and summer when bug populations are booming. In late summer, fruits may be more readily available as crops ripen, then in fall seeds and grains may be most abundant. In winter, any available food could be eaten, and birds may even eat nuts or grains they have cached. This adaptability allows birds to have a wider range of choices and take advantage of more food sources for better survival, particularly for resident species that do not migrate to different locations as local preferred foods dwindle.

Birds may also change their diets at different life stages based on changing nutritional needs. During the breeding season, for example, female birds often consume more calcium for healthier egg development. More animal-based foods may be present in birds' diets when they are molting and need more protein for for proper feather growth, and higher calorie, fat-rich foods are often preferred before and during migration, when the extra energy provides critical fuel for migratory species.

Many juvenile birds eat greater amounts of animal-based foods for the higher protein those foods provide, which improves growth and development. As the birds mature, they may eat a more varied diet or could even switch to a completely herbivorous menu, in which case they would not be considered truly omnivorous.


Data availability

All data used in this paper is deposted at: https://data.bris.ac.uk/data/dataset/awok7xqxmjyg2kr1m6op92w8e 88 . It includes the data used for time scaling the phylogeny, for running the principal components analysis of jaw shape coordinates, for visualizing the mechanical advantage values on a phylogeny, for performing Procrustes ANOVAs, and for performing the phylogenetic flexible discriminant analysis. The file Supplementary Data 1 is a spreadsheet that includes the list of taxa used in this study, their PC scores, mechanical advantage values (measured at jaw tip and m1), observed diet (extant mammals), proposed diet (extinct taxa), phylo FDA results (i.e., discriminant axis scores, predicted dietary class, and probability of belonging to a dietary group), first and last appearance dates, and references (photographs, diet and first and last appearance dates). The sources of all the specimens analyzed here are described in detail in Supplementary Data 1 they include museum collections (Institute of Paleobiology, Polish Academy of Sciences, Warsaw, Poland Oxford University Museum of Natural History, Oxford, United Kingdom Natural History Museum, London, United Kingdom Steinmann Institut, Universität Bonn, Bonn, Germany), online databases (Animal Diversity Web of the University of Michigan 49 [https://animaldiversity.org], the Natural History Museum online database [https://data.nhm.ac.uk] and the Field Museum online database [https://collections-zoology.fieldmuseum.org]) and photographs from the literature 1,2,5,15,23,28,33,35,36,38,50,51,52,53,54,55,56,57,58,59 .


Is Man An Herbivore? History of Veganism & Vegetarianism Prehistoric & Evolution Nutrition

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Sociality, Group Size, and Reproductive, Suppression among Carnivores

Scott Creel , David Macdonald , in Advances in the Study of Behavior , 1995

C SUMMARY OF PHYLOGENETIC REGRESSIONS

Our comparative analyses do not address all of the hypotheses we have reviewed (see Section VI,D ), but do allow us to confirm the general importance of several hypotheses for the entire order Carnivora.

The association between large groups and insectivory (and to a lesser degree omnivory and camivory) suggests that group living is favored by dependence on foods that are shared at little cost to a territory owner ( Waser, 1981 Macdonald, 1983 Carr and Macdonald, 1986 Macdonald and Carr, 1989 Rood, 1986 ). The result does not let us distinguish the relative importance of food abundance, dispersion, and renewal rate, because these variables are confounded with one another across diet types. We can conclude that one or more is likely to favor sociality.

Energetically costly reproduction is also associated with life in larger groups, lending indirect support to the hypothesis that sociality is favored in part through the benefits of alloparental care ( Gittleman, 1985a ). Where singletons or pairs have difficulty meeting the costs of reproduction, breeders will benefit directly from the presence of alloparents. If relatedness among adult group members is high, as appears common among carnivores (see Section III,E ), alloparents will gain indirect fitness through their efforts.

Costly reproduction is also associated with reproductive suppression of subordinates. Opportunities for subordinates to breed are often limited to marginal habitat, without a labor force of helpers, following risky dispersal ( Brown, 1987 Emlen, 1991 Waser and Jones, 1983 Waser et al., 1994 ). Together with such constraints, energetically costly reproduction raises the probability that the cost will exceed the expected benefit of a subordinate’s breeding attempt, and suppression should be tolerated ( Creel and Creel, 1991 ).


Additional files

Additional file 1: Tables S1-S4 and Figures S1-S2.

Whole-genome assemblies analyzed in the present study. Table S2. Bitter taste receptor genes TAS2Rs in the genome assemblies of Laurasiatherian mammals (Please refer to the excel file Supplementary_Table_S2, Additional file 3). Pseudogenes were listed in red characters. Whales and dolphins (Tutr, Oror, Live, Phma, Baac) which have lost most of the TAS2Rs were marked in pale read shadow, pangolin (Mape) which only have 2 TAS2Rs was marked in pale blue shadow, and the common shrew (Soar) with the most number of 52 TAS2Rs was marked in yellow shadow. Figure S1. (A and B) Dotplots comparing the Brandt’s bat and the big brown bat assemblies containing the clade of TAS2R16. (C and D) Dotplots comparing the Brandt’s bat and the big brown bat assemblies containing the clade of TAS2R18. (E and F) Dotplots comparing horse and cat assemblies containing the clades of TAS2R11 and TAS2R12. (G and H) Dotplots comparing horse and cat assemblies containing the clade of TAS2R62. The minimum repeat length was 100 bp and the repeat identity was 90 %. The TAS2Rs positions are shown by dashed lines. Figure S2. Forty PIC values converted from the 41 phylogenetically correlated data. Table S3. Classification of Truncated TAS2Rs in the genome assemblies of Laurasiatherian mammals. For each species, overlapping truncated TAS2Rs with similar orthologies in the multiple alignments were regarded as being derived from different loci. In contrast, non-overlapping TAS2Rs were regarded as being derived from the same loci with gap(s). Table S4. Birth genes and death genes in each branch of Laurasiatherian mammals. (PDF 0.99 mb)

Additional file 2:

Data set S1. Annotated sequences of TAS2Rs (Tas2rs) in the present study. The header of each FASTA sequence indicates the TAS2R name and its location in the contig, scaffold, or chromosome in the whole-genome assembly. Truncated and disrupted genes are indicated by T and P, respectively. (PDF 796 kb)