Types, evolution and significance of plant – animal interactions

Abstract  Interactions between plants and animals are analyzed starting from the advantages gained by animals and proceeding to those gained exclusively by plants. These interactions are essentially of five types: 1. predation of plants by animals; 2. benevolence of plants towards certain animals to prevent or reduce predation; 3. predation by plants (carnivorous plants); 4. symbiosis and mutualism; 5. seduction and deception of animals by plants for dispersal of plant reproductive structures. All types of plants are preyed on by animals, though from as far back in evolution as algae, certain plant molecules reduce or prevent predation. In the most primitive land plants, other types of interactions beneficial for plants are encountered. More evolved land plants (angiosperms) show all facets of the five types of interaction, whereas in prokaryotic and eukaryotic algae there is only predation and in some cases countermeasures to avoid it. An evolutionary path leading from predation, the original condition, to seduction, deception and carnivory, is also postulated. Keywords Plants, Animals, Predation, Benevolence, Symbiosis, Mutualism, Pollination, Seed dispersal Subject codes: Animal Ecology, Plant Ecology, Evolutionary Biology     

Evolutionary dynamics of biological auctions

Many scenarios in the living world, where individual organisms compete for winning positions (or resources), have properties of auctions. Here we study the evolution of bids in biological auctions. For each auction, n individuals are drawn at random from a population of size N. Each individual makes a bid which entails a cost. The winner obtains a benefit of a certain value. Costs and benefits are translated into reproductive success (fitness). Therefore, successful bidding strategies spread in the population. We compare two types of auctions. In “biological all-pay auctions”, the costs are the bid for every participating individual. In “biological second price all-pay auctions”, the cost for everyone other than the winner is the bid, but the cost for the winner is the second highest bid. Second price all-pay auctions are generalizations of the “war of attrition” introduced by Maynard Smith. We study evolutionary dynamics in both types of auctions. We calculate pairwise invasion plots and evolutionarily stable distributions over the continuous strategy space. We find that the average bid in second price all-pay auctions is higher than in all-pay auctions, but the average cost for the winner is similar in both auctions. In both cases, the average bid is a declining function of the number of participants, n. The more individuals participate in an auction the smaller is the chance of winning, and thus expensive bids must be avoided.     

Animal-Assisted Therapy Enhances Resident Social Interaction and Initiation in Long-Term Care Facilities

ABSTRACT

Social stimulation is a valuable aspect of therapeutic activities at long-term care facilities, designed to decrease social isolation, maintain or stimulate mental abilities, and increase awareness of the external environment. A study was undertaken at two such facilities to compare the effectiveness of Animal-Assisted Therapy (AAT) with Non-Animal Therapy (NAT) at providing social stimulation, that is, at providing opportunities for patients to engage in social interaction and to initiate social behaviors. While studies have indicated that AAT can improve resident outlook or affect, few have directly studied the social behaviors that might lead to such improvements, or the role the animals themselves might play. We observed 33 patients, both alert and semi- to non-alert, during regular recreational therapy sessions. Most patients were women (29 vs. four men), and geriatric (in their 70's and 80's). Non-Animal Therapies included Arts and Crafts and Snack Bingo, while AAT involved animals from local animal shelters being brought by volunteers to group sessions. Social behaviors naturally divided into Brief Conversations, Long Conversations, and Touch. We determined frequencies and rates of the behaviors, who initiated the behaviors and whether the behaviors were directed at other people or at the animals.

Overall, during AAT residents were involved in as much or more conversation with others, including the animals, as residents in Non-Animal Therapy, and were more likely to initiate and participate in longer conversations. The finding that different kinds of therapies seem to encourage different kinds of conversation might be an important consideration when investigating health benefits. The most dramatic differences between therapy types were found in rates of touch: touching the animals during AAT added significantly to resident engagement in, and initiation of, this behavior. Since touch is considered an important part of social stimulation and therapy, the enhancement of this social behavior by the animals is an important, and perhaps undervalued, effect.     

Floral scent and pollination in Browneopsis disepala (Leguminosae: Caesalpinioideae) in western Ecuador

Aspects of the pollination ecology of Browneopsis disepala, including floral scent composition, were studied. Floral scent was collected with head space techniques and analyzed by coupled gas chromatography-mass spectrometry. Inflorescence and flower development were followed, and amount and concentration of nectar measured. Flower-visiting animals were observed nocturally and diurnally. Inflorescences of B. disepala emit a floral scent that is typical of neither moth- nor bat-pollinated plants, but contains some compounds related to both pollination types. Nectar is produced in quantities and with sugar concentrations falling within a range typical of both moth- and bat-pollinated plants. The inflorescences are visited by both moths and bats, but the behavior of the bats suggests that they are the more efficient pollinators. Browneopsis disepala has a mixed pollination system and is dependent on animals for pollination.     

Behavior of dolphins towards adults and children during swim-with-dolphin programs and towards children with disabilities during therapy sessions

Abstract

In recent years, dolphin-assisted therapy has become very popular and an increasing number of facilities worldwide offer therapy programs with dolphins. In contrast to other animal-assisted therapy programs, dolphins are not domestic animals; they are mostly caught in the wild and there are still no studies on their behavior during these therapies. However, there is speculation that the behavior of dolphins toward people with mental and physical disabilities may play an important role in the success of the therapy. We observed 83 sessions with five untrained dolphins (Tursiops truncatus) at Dolphins Plus, a fenced area with ocean water in the Florida Keys, USA. Our detailed observations of contact and distance behavior between dolphins and different groups of swimmers (adults, children, and children with mental and physical disabilities) show that, in general, dolphins prefer small humans to adults. One dolphin showed a clear preference toward children with mental and physical disabilities, and we conclude that she showed assisting behavior.     

My Reflections on Understanding Animal Emotions for Improving the Life of Animals in Zoos

ABSTRACT

Scientists are often reluctant to attribute emotions to nonhuman animals that are similar to human emotions. When the author published her early studies, reviewers prohibited the word fear. Fearful behavior had to be described as agitated. The core emotional systems described by Panksepp may provide a useful framework for people who work hands-on with animals. The core systems are fear, rage, panic (separation distress), seek, lust, nurture, and play. Some scientists who deny that animals have real emotions often fail to review important areas of the literature. The areas that are sometimes left out are the effects of psychiatric medications on animals and genetic influences on differences in animal behavior. In both people and animals, genetics has an influence on both fearfulness and novelty seeking. Visualizing the seven core emotional systems as separate volume controls on a music mixing board may help zoo professionals determine the motivation of both normal and abnormal behavior. It may also help them to design more effective environmental enrichments.     

Effects of floor type,stocking density,slaughter age and gender on productive and qualitative traits of rabbits reared in collective pens

At 34 days of age, 376 crossbred rabbits of both sexes were housed in 16 open-top collective pens (1.68 m²) according to a 2×2×2 factorial arrangement with two types of pen floor (plastic v. wooden slatted), two stocking densities (12 v. 16 animals/m²) and two slaughter ages (76 v. 83 days). The rabbits were examined for growth performance, slaughter results and meat quality. The effect of gender was also examined. The percentage of rabbits with wounds due to aggression varied with stocking density (8.2% v. 26.2% for 12 v. 16 animals/m²; P⩽0.001), slaughter age (15.0% v. 22.0% at 76 v. 83 days; P⩽0.10) and gender (11.3% v. 25.8% for females v. males; P⩽0.001). Rearing rabbits on a plastic rather than a wooden slatted floor promoted slaughter weight (2795 v. 2567 g; P⩽0.001), dressing percentage (61.4% v. 60.9%; P⩽0.01), dissectible fat (2.4% v. 2.0%; P⩽0.01) and hind leg muscle-to-bone ratio (5.81 v. 5.35; P⩽0.001). Increased stocking density impaired daily growth (38.5 v. 35.9 g/day; P⩽0.05) and feed intake (140 v. 134 g/day; P⩽0.01) during the second period (55 days to slaughter) and decreased slaughter weight (2725 v. 2637 g; P⩽0.01). At the older slaughter age, the feed conversion ratio was impaired (2.98 v. 3.18; P⩽0.001); the slaughter weight (2574 g v. 2788 g; P⩽0.001), dissectible fat (2.0% v. 2.4%; P⩽0.01) and hind leg muscle-to-bone ratio (5.41 v. 5.75; P⩽0.01) increased; meat thawing losses, cooking losses and shear force decreased (P⩽0.05). The main differences between the females and males were found in the slaughter for transport losses (2.6% v. 2.2%; P⩽0.01) and longissimus lumborum proportions (13.0% v. 12.4%; P⩽0.01). In conclusion, the growth performance of pen-housed rabbits was largely determined by the type of floor and less affected by stocking density. The meat quality depended on ontogenetic factors, such as slaughter age and gender, and not on housing conditions. The differences in the percentages of wounded animals owing to experimental factors deserve further investigation from the perspective of animal welfare issues.     

Effect of coat color mutations on behavioral polymorphism in farm populations of American minks (<Emphasis Type="Italic">Mustela vison</Emphasis> Schreber, 1777) and sables (<Emphasis Type="Italic">Martes zibellina</Emphasis> Linnaeus, 1758)

Behavioral polymorphism estimated by the expression of the defensive reaction towards humans has been studied in farm-bred American minks and sables with different color types. Most animals (both minks and sables) from farm populations displayed passive defensive behavior towards humans in the standard hand catch test. Coat color genes have been found to have pleiotropic effects; they influence both the penetrance and expressivity of domestication behavior: in animals with aberrant color types (both sapphire minks and white-and-black sables), the proportion of animals with domestication behavior and the expressivity of this behavior are significantly higher (p < 0.01 and p < 0.001, respectively).     

Evolution and function of red pigmentation in land plants

BackgroundLand plants commonly produce red pigmentation as a response to environmental stressors, both abiotic and biotic. The type of pigment produced varies among different land plant lineages. In the majority of species they are flavonoids, a large branch of the phenylpropanoid pathway. Flavonoids that can confer red colours include 3-hydroxyanthocyanins, 3-deoxyanthocyanins, sphagnorubins and auronidins, which are the predominant red pigments in flowering plants, ferns, mosses and liverworts, respectively. However, some flowering plants have lost the capacity for anthocyanin biosynthesis and produce nitrogen-containing betalain pigments instead. Some terrestrial algal species also produce red pigmentation as an abiotic stress response, and these include both carotenoid and phenolic pigments.ScopeIn this review, we examine: which environmental triggers induce red pigmentation in non-reproductive tissues; theories on the functions of stress-induced pigmentation; the evolution of the biosynthetic pathways; and structure–function aspects of different pigment types. We also compare data on stress-induced pigmentation in land plants with those for terrestrial algae, and discuss possible explanations for the lack of red pigmentation in the hornwort lineage of land plants.ConclusionsThe evidence suggests that pigment biosynthetic pathways have evolved numerous times in land plants to provide compounds that have red colour to screen damaging photosynthetically active radiation but that also have secondary functions that provide specific benefits to the particular land plant lineage.     

Genetic variations in a population of herbivorous mites Tetranychus urticae in the production of the induced volatiles by kidney bean plants

Abstract

This study tested whether a population of herbivorous mites Tetranychus urticae exhibits genetic variation in the production of induced plant volatiles in kidney bean plants (Phaseolus vulgaris L.). We selected two T. urticae genotypes based on their dispersal behavior (early- and late-disperser) in two plant lines (Line-1 and Line-2). In both lines, plants infested by the early-disperser produced large amounts of induced volatiles after the spider mite population peaked on the plants, whereas those infested by the late-disperser emitted the largest amount of induced volatiles at the population peak. The possible manipulation of the production of herbivore-induced plant volatiles by herbivores is discussed.     

Le Infezioni Con “Stubborn” Ottenute per Trauma E Il Grado di Recettività dei Tipi di Grano

Abstract

Dioecy ensures cross pollination but pollen must travel from male to female plants, sometimes covering long distances. The present study concerns the reproductive strategy of two Italian dioecious plants: Mercurialis annua L. and Bryonia dioica L. The former is anemophilous and the latter is entomophilous; the latter has nectar and pollen as rewards. The distribution of pollen grains on the stigma is very different in the two species, reflecting the different types of pollination. In both species there is a number-dependent mechanism of pollen germination on the stigma. This mechanism could enhance male gametophytic competition.     

Medicinal plants as a fight against murine blood-stage malaria

ObjectiveMalaria is an infectious parasitic disease affecting most of countries worldwide. Due to antimalarial drug resistance, researchers are seeking to find another safe efficient source for treatment of malaria. Since many years ago, medicinal plants were widely used for the treatment of several diseases. In general, most application is done first on experimental animals then human. In this article, medicinal plants as antimalarial agents in experimental animals were reviewed from January 2000 until November 2020.Materials and methodsIn this systematic review published articles were reviewed using the electronic databases NCBI, ISI Web of knowledge, ScienceDirect and Saudi digital library to check articles and theses for M.Sc/Ph.D. The name of the medicinal plant with its taxon ID and family, the used Plasmodium species, plant part used and its extract type and the country of harvest were described.Results and conclusionThe reviewed plants belonged to 83 families. Medicinal plants of families Asteraceae, Meliaceae Fabaceae and Lamiaceae are the most abundant for use in laboratory animal antimalarial studies. According to region, published articles from 33 different countries were reviewed. Most of malaria published articles are from Africa especially Nigeria and Ethiopia. Leaves were the most common plant part used for the experimental malaria research. In many regions, research using medicinal plants to eliminate parasites and as a defensive tool is popular.     

Exploring the influence of plant and animal item contexts on student response patterns to natural selection multiple choice items

Background

Research has shown that students have a variety of ideas about natural selection that may be context dependent. Prior analyses of student responses to open-ended evolution items have demonstrated that students apply more core ideas about natural selection when asked about animals, but respond with the same number of naive ideas for plant and animal items. Other research has shown that changing an item to ask about trait loss or gain shifted the types of naive ideas applied by students in their responses. In this paper, we take up both of these findings to determine if differences exist in the types of ideas students apply to similar items with either a plant or an animal in the item stem.

Results

In order to understand if students applied different ideas to plants or animals in distractor-driven multiple-choice questions, we analyzed high school biology students’ responses to matched-item pairs. Dichotomous scoring revealed that students chose the correct response more often for the animal items as compared to the plant items. Chi squared analyses revealed significant differences in the distribution of student responses to matched items. For example, more students chose responses that defined animal fitness as related to their strength and plants’ fitness related to its longevity.

Conclusions

These results suggest that varied context of plants or animals in item stems on diagnostic assessments can provide teachers with a more complete picture of their students’ ideas about natural selection prior to instruction. This is particularly important in assessments used prior to instruction; as teachers will gain greater insight into the variety of ways students think about natural selection across different types of plants and animals.

     

Food preference of freshwater invertebrates: comparing fresh and decomposed angiosperm and a filamentous alga

1. Fresh and decomposed Mougeotia sp. (a filamentous green alga) and Elodea nuttallii (a vascular plant) were offered as food to three species of aquatic macroinvertebrates (Lymnaea peregra, Asellus meridianus and Endochironomus albipennis) to test: (i) if filamentous algae are preferred to aquatic higher plants (hereafter, called ‘macrophytes’) and (ii), as is known for higher plants, if decomposition also results in greater palatability of filamentous algae. 2. Compared with the alga, the macrophyte in both states was of higher nutritional value. Conditioning improved the nutritional value of both food types, but especially of the macrophyte. 3. Both fresh alga and fresh macrophyte were eaten little by all animals except A. meridianus feeding upon the macrophyte. Consumption was higher for both plants in their decomposed state. However, L. peregra consumed more decomposed macrophyte than the decomposed alga. Both decomposed plants were eaten most by E. albipennis followed by A. meridianus and L. peregra. 4. Digestibility of both plants, but especially of the macrophyte, increased significantly after decomposition. The assimilation efficiencies of all animals on the fresh E. nuttallii were higher than on fresh Mougeotia sp. After decomposition, the efficiency increased significantly only on the alga. Consequently, both decomposed plants were assimilated with similar efficiency by all test animals. 5. Amongst aquatic macrophytes, the increase of their consumption and digestibility upon decomposition has hitherto been known only for vascular plants but not for filamentous algae.     

Clostridium difficile in young farm animals and slaughter animals in Belgium

Faecal carriage of Clostridium difficile in healthy animals has been reported recently, especially in piglets and calves. However there is limited data about carriage in animals just prior to slaughter in Europe. The main objective of this study was to determine the presence of C. difficile in pigs and cattle at the slaughterhouse. C. difficile was isolated in 6.9% of the cattle at the slaughterhouse. None of the pig slaughter samples were positive for C. difficile after an enrichment time of 72 h. For complementary data, a short study was conducted in piglets and calves at farms. C. difficile was more prevalent in piglets (78.3%) than in calves (22.2%) on the farms. Regarding the piglet samples, 27.8% of the positive samples were detected without enrichment of stools. The PCR ribotype 078 was predominant in farm animals. Samples isolated from slaughter cattle presented the widest range in PCR-ribotype variety, and the most prevalent PCR ribotype was 118a UCL. The results of this study confirm that C. difficile is present in slaughter animals in Belgium with a large percentage of toxigenic strains also commonly found in humans.     

Physiological mechanisms in the control of bioluminescent countershading in a midwater shrimp

In the oceanic midwater environment, most animals have evolved an extraordinary anti‐predation behavior using bioluminescent countershading (counterillumination) to help them remain cryptic to visual predators. For the midwater penaeid shrimp, Sergestes similis, the interaction of both hormonal and neural systems may be involved in the control of counterillumination. S. similis responds to downward‐directed illumination, detected by the eyes, with light emission from five hepatic light organs. Dark‐adapted specimens undergo a slow induction process prior to production of the conventional counterillumination response. The induction of bio‐luminescence may involve a hormonal pathway mediated by the light‐adapting retinal distal pigment dispersing hormone. Once induced, the rapid control of counterillumination may involve a neural pathway. Because counterilluminating animals directly respond to their optical environment, an understanding of the control of bioluminescence provides an insight into the poorly understood visual processing capabilities of deep‐sea animals.     

Applications of nanobodies in plant science and biotechnology

Key message

Present review summarizes the current applications of nanobodies in plant science and biotechnology, including plant expression of nanobodies, plant biotechnological applications, nanobody-based immunodetection, and nanobody-mediated resistance against plant pathogens.

Abstract

Nanobodies (Nbs) are variable domains of heavy chain-only antibodies (HCAbs) isolated from camelids. In spite of their single domain structure, nanobodies display many unique features, such as small size, high stability, and cryptic epitopes accessibility, which make them ideal for sophisticated applications in plants and animals. In this review, we summarize the current applications of nanobodies in plant science and biotechnology, focusing on nanobody expression in plants, plant biotechnological applications, determination of plant toxins and pathogens, and nanobody-mediated resistance against plant pathogens. Prospects and challenges of nanobody applications in plants are also discussed.

     

Interaction between bacterial enteric pathogens and aquatic macrophytes. Can Salmonella be internalized in the plants used in phytoremediation processes?

Abstract

The environment is considered a reservoir of pathogens and a possible source of infection for animals and humans. The association between enteric pathogens and food plants has been demonstrated in several studies, while few studies have addressed possible interactions between human pathogens and aquatic plants. This study, performed by setting mesocosms, evaluates the interaction between an enteric pathogen (Salmonella enterica serovar Napoli, S. Napoli) and a macrophyte (Phragmites australis (Cav.) Trin. ex Steudel) and the possible ability of the bacterium to internalize into the plant. The results show that S. Napoli concentration decreased gradually in growth solution without plants (control) while it was able to persist adhering to submerged parts of plants in treated mesocosms. The adhesion of the bacterium remained stable for 20?days, then decreased gradually until the end of the experiment. In addition, S. Napoli was able to internalize and colonize stems and leaves. In conclusion, the study suggests that macrophytes can represent an alternative environmental reservoir of pathogens for humans and animals. The adhesion to roots and rhizomes and the internalization could contribute to the bacterial persistence in the aquatic ecosystems by playing an important role in ecology and transmission of pathogens.