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Seed Dispersal Syndrome
Seed dispersal syndromes are morphological characters of seeds correlated to particular seed dispersal agents.Clobert, J., Le Galliard, J.F., Cote, J., Meylan, S. & Massot, M. (2009). Informed dispersal, heterogeneity in animal dispersal syndromes and the dynamics of spatially structured populations. Ecology Letters, 12, 197–209.Griz, L.M.S. & Machado, I.C.S. (2001). Fruiting phenology and seed dispersal syndromes in caatinga, a tropical dry forest in the northeast of Brazil. Journal of Tropical Ecology, 17, 303–321.Link, A. & Stevenson, P.R. (2004). Fruit dispersal syndromes in animal disseminated plants at Tinigua National Park, Colombia. Revista Chilena de Historia Natural, 77, 319–334.Tamboia, T., Cipollini, M.L. & Levey, D.J. (1996). An Evaluation of Vertebrates Seed Dispersal Syndromes in Four Species of Black Nightshade. Oecologia, 107(4), 522–532. Dispersal is the event by which individuals move from the site of their parents to establish in a new area. Herrera, C. M. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seed
In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds are the product of the ripened ovule, after the embryo sac is fertilization, fertilized by Pollen, sperm from pollen, forming a zygote. The embryo within a seed develops from the zygote and grows within the mother plant to a certain size before growth is halted. The formation of the seed is the defining part of the process of reproduction in seed plants (spermatophytes). Other plants such as ferns, mosses and marchantiophyta, liverworts, do not have seeds and use water-dependent means to propagate themselves. Seed plants now dominate biological Ecological niche, niches on land, from forests to grasslands both in hot and cold climates. In the flowering plants, the ovary ripens into a fruit which contains the seed and serves to disseminate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foraging
Foraging is searching for wild food resources. It affects an animal's fitness because it plays an important role in an animal's ability to survive and reproduce. Foraging theory is a branch of behavioral ecology that studies the foraging behavior of animals in response to the environment where the animal lives. Behavioral ecologists use economic models and categories to understand foraging; many of these models are a type of optimal model. Thus foraging theory is discussed in terms of optimizing a payoff from a foraging decision. The payoff for many of these models is the amount of energy an animal receives per unit time, more specifically, the highest ratio of energetic gain to cost while foraging. Foraging theory predicts that the decisions that maximize energy per unit time and thus deliver the highest payoff will be selected for and persist. Key words used to describe foraging behavior include ''resources'', the elements necessary for survival and reproduction which have a l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peru
Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pacific Ocean. Peru is a Megadiverse countries, megadiverse country, with habitats ranging from the arid plains of the Pacific coastal region in the west, to the peaks of the Andes mountains extending from the north to the southeast of the country, to the tropical Amazon basin rainforest in the east with the Amazon River. Peru has Demographics of Peru, a population of over 32 million, and its capital and largest city is Lima. At , Peru is the List of countries and dependencies by area, 19th largest country in the world, and the List of South American countries by area, third largest in South America. Pre-Columbian Peru, Peruvian territory was home to Andean civilizations, several cultures during the ancient and medieval periods, and has one o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Husk
Husk (or hull) in botany is the outer shell or coating of a seed. In the United States, the term husk often refers to the leafy outer covering of an Ear (botany), ear of maize (corn) as it grows on the plant. Literally, a husk or hull includes the protective outer covering of a seed, fruit, or vegetable. It can also refer to the exuvia of insects or other small animals left behind after ecdysis, moulting. The term ''husk'' dates to c.14, it is probably based on Middle Dutch word ''huusken'' meaning 'little house', which is derived from ''hūs'' meaning house. In cooking, hull can also refer to other waste parts of fruits and vegetables, notably the cap or sepal of a strawberry. Grains such as wheat and barley have husks. The grains are the entire seed of a plant. The seed of a grain (which the grain industry calls a "Seed, kernel") is made up of three key edible parts – the bran, the wheat germ, germ, and the endosperm – which are all protected by an inedible husk that pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flower
Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, modified leaves; corolla, the petals; androecium, the male reproductive unit consisting of stamens and pollen; and gynoecium, the female part, containing style and stigma, which receives the pollen at the tip of the style, and ovary, which contains the ovules. When flowers are arranged in groups, they are known collectively as inflorescences. Floral growth originates at stem tips and is controlled by MADS-box genes. In most plant species flowers are heterosporous, and so can produce sex cells of both sexes. Pollination mediates the transport of pollen to the ovules in the ovaries, to facilitate sexual reproduction. It can occur between different plants, as in cross-pollination, or between flowers on the same plant or even the same f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion
Adhesion is the tendency of dissimilar particles or interface (matter), surfaces to cling to one another. (Cohesion (chemistry), Cohesion refers to the tendency of similar or identical particles and surfaces to cling to one another.) The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are also certain emergent mechanical effects. Surface energy Surface energy is conventionally defined as the work (physics), work that is required to build an area of a particular surface. Another way to view the surface energy is to relate it to the work required to cleave a bulk sample, creating two surfaces. If the new surfaces are identical, the surface energy γ of each surface is equal to h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitat
In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as Biophysical environment, environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and Luminous intensity, light intensity. Biotic index, Biotic factors include the availability of food and the presence or absence of Predation, predators. Every species has particular habitat requirements, habitat generalist species are able to thrive in a wide array of environmental conditions while habitat specialist species require a very limited set of factors to survive. The habitat of a species is not necessarily found in a ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Competition (biology)
Competition is an Biological interaction, interaction between organisms or species in which both require one or more Resource (biological), resources that are in Limiting factor, limited supply (such as food, water, or Territory (animal), territory). Competition lowers the Fitness (biology), fitness of both organisms involved since the presence of one of the organisms always reduces the amount of the resource available to the other. In the study of community ecology, competition within and between members of a species is an important biological interaction. Competition is one of many interacting Biotic component, biotic and Abiotic component, abiotic factors that affect Community (ecology), community structure, species diversity, and population dynamics (shifts in a population over time). There are three major Mechanism (biology), mechanisms of competition: interference, exploitation, and apparent competition (in order from most direct to least direct). Interference and exploitat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotype
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology (physical form and structure), its developmental processes, its biochemical and physiological properties, and its behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code (its genotype) and the influence of environmental factors. Both factors may interact, further affecting the phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and again in his 1982 book '' The Extended Phenotype'' suggested that one can regard bird nests and other built structures such as caddisfly larva cases and beaver dams ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod
Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metamerism (biology), metameric) Segmentation (biology), segments, and paired jointed appendages. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. They form an extremely diverse group of up to ten million species. Haemolymph is the analogue of blood for most arthropods. An arthropod has an open circulatory system, with a body cavity called a haemocoel through which haemolymph circulates to the interior Organ (anatomy), organs. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. They have ladder-like nervous systems, with paired Anatomical terms of location#Dorsal and ventral, ventral Ventral nerve cord, nerve cord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthesis
Photosynthesis ( ) is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism. ''Photosynthesis'' usually refers to oxygenic photosynthesis, a process that produces oxygen. Photosynthetic organisms store the chemical energy so produced within intracellular organic compounds (compounds containing carbon) like sugars, glycogen, cellulose and starches. To use this stored chemical energy, an organism's cells metabolize the organic compounds through cellular respiration. Photosynthesis plays a critical role in producing and maintaining the oxygen content of the Earth's atmosphere, and it supplies most of the biological energy necessary for complex life on Earth. Some bacteria also perform anoxygenic photosynthesis, which uses bacteriochlorophyll to split hydrogen sulfide as a reductant instead of water, p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selection Pressure
Evolutionary pressure, selective pressure or selection pressure is exerted by factors that reduce or increase reproductive success in a portion of a population, driving natural selection. It is a quantitative description of the amount of change occurring in processes investigated by evolutionary biology, but the formal concept is often extended to other areas of research. In population genetics, selective pressure is usually expressed as a selection coefficient. Amino acids selective pressure It has been shown that putting an amino acid bio-synthesizing gene like ''HIS4'' gene under amino acid selective pressure in yeast causes enhancement of expression of adjacent genes which is due to the transcriptional co-regulation of two adjacent genes in Eukaryota. Antibiotic resistance Drug resistance in bacteria is an example of an outcome of natural selection. When a drug is used on a species of bacteria, those that cannot resist die and do not produce offspring, while those that s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
