We are searching data for your request:
Upon completion, a link will appear to access the found materials.
Has anyone seen this before? I got it from India as a gift but I have no idea what it is called or how to take care of it. Thanks
Looks very similar to Naringi crenulata which is found in India. More information can be found on this Encyclopedia of Life page.
Image source: https://commons.wikimedia.org/wiki/File:Naringi_crenulata_leaves_and_flowers.jpg">
I believe that the scientific name of that leaf is Aegle marmelos. I think that a good place to start is by reverse searching the Google image and then seeing if there is a scientific name associated with it. If there is not a scientific name associated with it, you can search for the scientific name based on the organism's common name.
Following on from Kurt's response, there is a similar irregular margin version called Hesperethusa crenulata which is perhaps apparently used as a beauty cream, Thanaka, unverifiably promoted as "skin whitening" i.e. bleaching by some sellers, antioxidant, antibacterial and moisturizing, mostly famous in Burma, and which can be bought around the world. So it's also a cultivated tree and you'll find a lot of common and cultivar names for it. the sources of information for it are confused, there seems to be Limonia Acidissima and Limonia crenulata which are closely related. Perhaps both are used medicinally.
Thanaka also appears as Thanaka tree with reference to Hesperethusa so it seems that it has some Natural remedy / Ayurveda properties from the same plant in Burma and India.
In depth page for it here: http://idtools.org/id/citrus/citrusid/factsheet.php?name=Hesperethusa+crenulata
one with bark havested
Our editors will review what you’ve submitted and determine whether to revise the article.
Spinach, (Spinacia oleracea), hardy leafy annual of the amaranth family (Amaranthaceae), used as a vegetable. Widely grown in northern Europe and the United States, spinach is marketed fresh, canned, and frozen. It received considerable impetus as a crop in the 1920s, when attention was first called to its high content of iron and vitamins A and C. Spinach is served as a salad green and as a cooked vegetable.
The edible leaves are arranged in a rosette, from which a seed stalk emerges. The simple leaves are somewhat triangular or ovate and may be flat or puckered. The flowers are inconspicuous and produce small dry fruits. Spinach requires cool weather and deep, rich, well-limed soil to give quick growth and maximum leaf area. Seed can be sown every two weeks from early spring to late summer, in rows 30 cm (12 inches) apart, the plantlets being thinned in the row. The last sowings produce young plants that yield a crop in the autumn and stand over the winter, providing leaves in early spring or even through the winter if the weather is not too severe.
Psidium guajava may be confused with Psidium guineense (Brazilian guava) and Psidium cattleianum (strawberry guava). These species can be distinguished by the following differences:
- P. guajava has hairy (pubescent) younger stems that are four-angled in cross-section (quadrangular) and relatively large yellow fruit (2.5-10 cm long). Its flowers are usually borne singly (occasionally in threes) in the leaf forks (axils) and its somewhat hairy (pubescent) dull green leaves have 10-20 pairs of prominent side veins (lateral veins).
- P. guineense has hairy (pubescent) younger stems that are almost rounded in cross-section (sub-cylindrical) and relatively small yellow fruit (1-2.5 cm long). Its flowers are usually borne in threes (occasionally singly) in the leaf forks (axils) and its hairy (pubescent) dull green leaves have 6-10 pairs of side veins (lateral veins).
- P. cattleianum has hairless (glabrous) younger stems that are rounded in cross-section (cylindrical) and relatively small purplish-red or yellow fruit (2-4 cm long). Its flowers are borne singly in the leaf forks (axils) and its hairless (glabrous) glossy green leaves have 6 or 7 pairs of side veins (lateral veins).
/>Plant Management in Florida Waters
People use common names or scientific names when referring to particular plants (and animals). Both naming conventions serve a purpose.
Common names for plants and animals are used by local people. Common names may be totally different from one country to another, from one state to another, and even from one county to another. Common names change as new people move to an area, or as old common names fall out of favor for one reason or another.
Scientific names, on the other hand, are unique plant and animal names used across the world by scientists and other professionals regardless of the language they speak or write, because scientific names are always Latin or Latinized words. They are standardized, using the same name for the same organism and are always used in published research. Scientific names cannot be changed except by international scientific agreement.
You don't have to be a scientist to use scientific names. Scientific names reduce confusion and make communication much more certain.
Nuphar advena (a.k.a. bonnet, cow-lily, spatterdock)
In most of Florida, the floating-leaved plant Nuphar advena is also known by several common names: bonnet, cow lily, and spatterdock. This species is known by anglers to attract a variety of fish. Think how confusing it can be to discuss fishing if the plant's common name varies from county to county and state to state. Think how confusing it can be if you and your neighbors on the lake all have different names for the same plant.
Brasenia schreberi (a.k.a. snot bonnet or watershield)
In some places, our cattails are called bulrushes. Our bulrushes are their club rushes their rice grass is our cut grass. And often the same common name is used for different plants.
Furthermore, sawgrass is not a grass—it is a sedge. And bald-rushes, beak-rushes, bulrushes, club-rushes, lake rushes, spikerushes and star-rushes are not true rushes but sedges. (In fact, the only true rushes in Florida are the bog rushes of the genus, Juncus.) Common names vary in other ways too. Plant nurseries, garden centers, aquarium shops, and other plant retailers often assign popular common names to plants they sell. It's easier to sell "watershield" than Brasenia schreberi.
Panicum repens (at left) is a non-native invasive plant. Panicum hemitomon (at right) is a desirable native plant.
A scientific name is used by botanists, growers, plant managers, and others to avoid the confusion caused by common names. Professional plant taxonomists assign a unique scientific name to each plant. The naming system was invented by the Swedish botanist Linnaeus in the 1700s. It is based on the science of taxonomy, and uses a hierarchical system called binomial nomenclature.
Taxonomy is the classification of organisms. Plant and animal taxonomy is arranged in a hierarchy, from the broadest level of phylum down to the most specific, species:
– Phylum or Division
A species is a group of individuals that do not successfully interbreed with individuals of other groups.
A genus is a group of closely related species. Species within a genus can look alike or vastly different. It is not advisable to make generalizations about a plant’s invasiveness based on genus alone. One species of a genus may be greatly beneficial while another species of the same genus may be an invasive nuisance.
Conventions for Using Common and Scientific Names
In common names, the words are not capitalized unless a word is a proper noun. For example: maidencane, bulrush, water hyacinth, Florida pondweed, duckweed and hydrilla.
Scientific names are usually based on Latin or Greek words and are written in italics or underlined. For example, the aquatic plant whose common name in Florida is maidencane has the scientific name Panicum hemitomon or Panicum hemitomon .
A scientific name has two (or sometimes more) parts. The first part is the genus name and the second part is the species. For example, Potamogeton floridanus is the scientific name for a species of pondweed. Potamogeton is the genus and floridanus is the species. Potamogeton illinoensis is a different species of pondweed. By using scientific names containing both genus and species, people can be very sure of the species they are referring to. The term “Eleocharis spp.” refers to all 150 species in the Eleocharis genus. Naming may become even more complex by further classifications such as subspecies and varieties.
In scientific names, the first word (genus) is capitalized and the following words (species, subspecies, etc.) are not capitalized. For example: Pistia stratiotes (water lettuce), Scirpus americanus (American bulrush), and Saururus cernuus (lizard's tail).
Almost everyone pronounces the Latin and Greek scientific name differently. Professional botanists are usually considered the experts.
What is the scientific name of this leaf? - Biology
Common Name: Squawroot
Scientific Name: Conopholis americana
(The information for this species page was gathered in part by Ms. Carol McKenzie for Biology 220W during Spring 2009 at Penn State New Kensington)
Squawroot (Conopholis americana) (also called “cancer root” or “bear cone”) is a low growing, brown, scaly plant that reaches heights of one foot at maturity. It is found often in dense clusters in oak and beech forests throughout eastern North America. The plants most closely resemble brown, scaly pine cones protruding up out of the ground. Image credit: Deborah Sillman.
Squawroot is a non-photosynthetic plant that relies on a parasitic connection to the roots of host trees (most species of oak and also beech) for its nourishment. It is a perennial that lives up to ten years. Most of the plants biomass is found underground. The cone-like structures that we see are its small, specialized, flowering stems.
Squawroot is more common in older forests, and its presence and relative abundance in a site may be significant indicators of forest age and stability. In areas where oak forests are being replaced by secondary forests that are dominated by maples or other non-oak tree species, squawroot is an increasingly uncommon and possibly threatened plant.
It is not clear in the literature if squawroot seriously compromises the health of its host tree. It is likely that it, by itself, may exist in a very stable parasite host symbiosis with its much larger and longer lived host oak or beech tree. But, if other stresses combine with squawroot’s presence, the health and vitality of the host tree may be reduced.
A squawroot seedling grows underground for approximately four years. During this time the roots of the seedling attach to the roots of its host tree forming large, swollen knobs (possibly the source of the name “cancer root”). At four years, the plant sends up its scaly, flowering stems. Yellow to cream-colored flowers develop on these stems. These flowers produce a scent that has been variously described as something between carrion and cabbage. Flies and bumblebees are the primary pollinators of squawroot.
Uses by Other Animals
Both the seeds and the aging stalks are consumed by many mammals including white-tailed deer and black bear (hence the name “bear cone”). The seeds are widely dispersed in the feces of these mammals.
Squawroot can be consumed both as a food and also as a folk medicine. The above ground stalks may be eaten directly or dried to brew teas. The plant has astringent properties and estrogen-like activities. It was used by Native Americans to treat menopause symptoms, bleeding in the bowel and uterus, and headaches.
What is the scientific name of this leaf? - Biology
The diamondback moth is probably of European origin but is now found throughout the Americas and in Europe, Southeast Asia, Australia, and New Zealand. It was first observed in North America in 1854, in Illinois, but had spread to Florida and the Rocky Mountains by 1883, and was reported from British Columbia by 1905. In North America, diamondback moth is now recorded everywhere that cabbage is grown. However, it is highly dispersive, and is often found in areas where it cannot successfully overwinter, including most of Canada.
Figure 1. Larva of the diamondback moth, Plutella xylostella (Linnaeus). Photograph by Lyle Buss, University of Florida.
Description (Back to Top)
Egg: Diamondback moth eggs are oval and flattened, and measure 0.44 mm long and 0.26 mm wide. Eggs are yellow or pale green in color, and are deposited singly or in small groups of two to eight eggs in depressions on the surface of foliage, or occasionally on other plant parts. Females may deposit 250 to 300 eggs but average total egg production is probably 150 eggs. Development time averages 5.6 days.
Larva: The diamondback moth has four instars. Average and range of development time is about 4.5 (3-7), 4 (2-7), 4 (2-8), and 5 (2-10) days, respectively. Throughout their development, larvae remain quite small and active. If disturbed, they often wriggle violently, move backward, and spin down from the plant on a strand of silk. Overall length of each instar rarely exceeds 1.7, 3.5, 7.0, and 11.2 mm, respectively, for instars 1 through 4. Mean head capsule widths for these instars are about 0.16, 0.25, 0.37, and 0.61 mm. The larval body form tapers at both ends, and a pair of prolegs protrudes from the posterior end, forming a distinctive "V". The larvae are colorless in the first instar, but thereafter are green. The body bears relatively few hairs, which are short in length, and most are marked by the presence of small white patches. There are five pairs of prolegs. Initially, the feeding habit of first instar larvae is leaf mining, although they are so small that the mines are difficult to notice. The larvae emerge from their mines at the conclusion of the first instar, molt beneath the leaf, and thereafter feed on the lower surface of the leaf. Their chewing results in irregular patches of damage, and the upper leaf epidermis is often left intact.
Pupa: Pupation occurs in a loose silk cocoon, usually formed on the lower or outer leaves. In cauliflower and broccoli, pupation may occur in the florets. The yellowish pupa is 7 to 9 mm in length. The duration of the cocoon averages about 8.5 days (range five to 15 days).
Figure 2. Pupa of the diamondback moth, Plutella xylostella (Linnaeus). Photograph by Lyle Buss, University of Florida.
Adult: The adult is a small, slender, grayish-brown moth with pronounced antennae. It is about 6 mm long, and marked with a broad cream or light brown band along the back. The band is sometimes constricted to form one or more light-colored diamonds on the back, which is the basis for the common name of this insect. When viewed from the side, the tips of the wings can be seen to turn upward slightly. Adult males and females live about 12 and 16 days, respectively, and females deposit eggs for about 10 days. The moths are weak fliers, usually flying within 2 m of the ground, and not flying long distances. However, they are readily carried by the wind. The adult is the overwintering stage in temperate areas, but moths do not survive cold winters such as is found in most of Canada. They routinely re-invade these areas each spring, evidently aided by southerly winds.
Figure 3. Adult diamondback moth, Plutella xylostella (Linnaeus). Photograph by Lyle Buss, University of Florida.
Detailed biology of diamondback moth can be found in Marsh (1917) and Harcourt (1955, 1957, 1963). A survey of the world literature was published by Talekar et al. (1985). A recent review of biology and management is provided by Philips et al. (2014).
Life Cycle (Back to Top)
Total development time from the egg to pupal stage averages 25 to 30 days, depending on weather, with a range of about 17 to 51 days. The number of generations varies from four in cold climates such as southern Canada to perhaps eight to 12 in the south. Overwintering survival is positively correlated with the abundance of snowfall in northern climates.
Host Plants (Back to Top)
Diamondback moth attacks only plants in the family Cruciferae. Virtually all cruciferous vegetable crops are eaten, including broccoli, Brussels sprouts, cabbage, Chinese cabbage, cauliflower, collard, kale, kohlrabi, mustard, radish, turnip, and watercress. Not all are equally preferred, however, and collard will usually be chosen by ovipositing moths relative to cabbage. Several cruciferous weeds are important hosts, especially early in the season before cultivated crops are available.
Damage (Back to Top)
Plant damage is caused by larval feeding. Although the larvae are very small, they can be quite numerous, resulting in complete removal of foliar tissue except for the leaf veins. This is particularly damaging to seedlings, and may disrupt head formation in cabbage, broccoli, and cauliflower. The presence of larvae in florets can result in complete rejection of produce, even if the level of plant tissue removal is insignificant.
Diamondback moth was long considered a relatively insignificant pest. Its impact was overshadowed by such serious defoliators as imported cabbageworm, Pieris rapae (Linnaeus), and cabbage looper, Trichoplusia ni (Hubner). However, in the 1950s the general level of abundance began to increase, and by the 1970s it became troublesome to crucifers in some areas. Insecticide resistance was long suspected to be a component of the problem. This was confirmed in the 1980s as pyrethroid insecticides began to fail, and soon thereafter virtually all insecticides were ineffective. Relaxation of insecticide use, and particularly elimination of pyrethroid use, can return diamondback moth to minor pest status by favoring survival of parasitoids.
Natural Enemies (Back to Top)
Large larvae, prepupae, and pupae are often killed by the parasitoids Microplitis plutellae (Muesbeck) (Hymenoptera: Braconidae), Diadegma insulare (Cresson) (Hymenoptera: Ichneumonidae), and Diadromus subtilicornis (Gravenhorst) (Hymenoptera: Ichneumonidae). All are specific on Plutella xylostella. The larval parasitoids Diadegma insulare (Cresson) (Hymenoptera: Ichneumonidae) and Microplites plutellae (Muesebeck) (Hymenoptera: Braconidae) are quite important in North America (Philips et al. 2014). In warmer climates such as the southeastern USA, Oomyzus sokolowski (Kurdjumov) (Hymenoptera: Eulophidae) assumes importance as a larval parasitoid. Nectar produced by wildflowers is important in determining parasitism rates by Diadegma insulare. Egg parasites are unknown. Fungi, granulosis virus, and nuclear polyhedrosis virus sometimes occur in high density diamondback moth larval populations.
Weather (Back to Top)
A large proportion of young larvae are often killed by rainfall. However, the most important factor determining population trends is thought to be adult mortality. Adult survival was thought to be principally a function of weather, although this hypothesis has not been examined rigorously.
Management (Back to Top)
Sampling: Populations are usually monitored by making counts of larvae, or by the level of damage. In Texas, average population densities of up to 0.3 larvae per plant are considered to be below the treatment level. In Florida and Georgia, treatment is recommended only when damage equals or exceeds one hole per plant. When growers monitor fields and subscribe to these treatment thresholds rather than trying to prevent any insects or damage from occurring in their fields, considerably fewer insecticide applications are needed to produce a satisfactory crop. A minimum plant sample size of 40 to 50 is recommended except for the egg stage, where 150 plants should be examined for accurate population estimates.
Pheromone traps can be used to monitor adult populations, and may predict larval populations 11 to 21 days later. Because of variation among locations, each crop field requires independent monitoring.
Insecticides: Protection of crucifer crops from damage often requires application of insecticide to plant foliage, sometimes as frequently as twice per week. However, resistance to insecticides is widespread, and includes most classes of insecticides including some Bacillus thuringiensis products. Rotation of insecticide classes is recommended, and the use of Bacillus thuringiensis is considered especially important because it favors survival of parasitoids. Even Bacillus thuringiensis products should be rotated, and current recommendations generally suggest alternating the kurstaki and aizawa strains because resistance to these microbial insecticides occurs in some locations. Mixtures of chemical insecticides, or chemicals and microbials, are often recommended for diamondback moth control. This is due partly to the widespread occurrence of resistance, but also because pest complexes often plague crucifer crops, and the insects vary in susceptibility to individual insecticides.
Cultural practices: Rainfall has been identified as a major mortality factor for young larvae, so it is not surprising that crucifer crops with overhead sprinkle irrigation tend to have fewer diamondback moth larvae than drip or furrow-irrigated crops. Best results were obtained with daily evening applications.
Crop diversity can influence abundance of diamondback moth. Larvae generally are fewer in number, and more heavily parasitized, when crucifer crops are interplanted with another crop or when weeds are present. This does not necessarily lead to reduction in damage, however. Surrounding cabbage crops with two or more rows of more preferred hosts such as collard and mustard can delay or prevent the dispersal of diamondback moth into cabbage crops.
Crucifer transplants are often shipped long distances prior to planting, and diamondback moth may be included with the transplants. In the United States, many transplants are produced in the southern states, and then moved north as weather allows. Cryptic insects such as young diamondback moth larvae are sometimes transported, and inoculated in this manner. The transport of insecticide-resistant populations also may occur. Every effort should be made to assure that transplants are free of insects prior to planting.
Host Plant Resistance (Back to Top)
Crucifer crops differ somewhat in their susceptibility to attack by diamondback moth. Mustard, turnip, and kohlrabi are among the more resistant crucifers, but resistance is not as pronounced as it is for imported cabbageworm and cabbage looper . Varieties also differ in susceptibility to damage by diamondback moth, and a major component of this resistance is the presence of leaf wax. Glossy varieties, lacking the normal waxy bloom and therefore green rather than grayish green, are somewhat resistant to larvae. Larvae apparently spend more time searching, and less time feeding, on glossy varieties. Glossy varieties also tend to have fewer imported cabbageworm larvae and cabbage aphids, but more cabbage flea beetles.
Selected References (Back to Top)
- Cartwright B, Edelson JV, Chambers C. 1987. Composite action thresholds for the control of lepidopterous pests on fresh-market cabbage in the lower Rio Grande Valley of Texas. Journal of Economic Entomology 80: 175-181.
- Harcourt DG. 1955. Biology of the diamondback moth, Plutella maculipennis (Curt.) (Lepidoptera: Plutellidae), in eastern Ontario. Report of the Quebec Society for the Protection of Plants 37: 155-160.
- Harcourt DG. 1957. Biology of the diamondback moth, Plutella maculipennis (Curt.) (Lepidoptera: Plutellidae), in Eastern Ontario. II. Life-history, behaviour, and host relationships. Canadian Entomologist 89: 554-564.
- Harcourt DG. 1963. Major mortality factors in the population dynamics of the diamondback moth, Plutella maculipennis (Curt.) (Lepidoptera: Plutellidae). Memoirs of the Entomological Society of Canada 32: 55-66.
- Marsh HO. 1917. Life history of Plutella maculipennis, the diamond-back moth. Journal of Apicultural Research 10: 1-10.
- McHugh Jr. JJ, Foster RE. 1995. Reduction of diamondback moth (Lepidoptera: Plutellidae) infestation in head cabbage by overhead irrigation. Journal of Economic Entomology 88: 162-168.
- Philips CR, Fu Z, Kuhar TP, Shelton AM, Cordero RJ. 2014. Natural history, ecology, and management of diamondback moth (Lepidoptera: Plutellidae), with emphasis on the United States. Journal of Integrated Pest Management 5 (3).
- Stoner KA. 1990. Glossy leaf wax and plant resistance to insects in Brassica oleracea under natural infestation. Environmental Entomology 19: 730-739.
- Talekar NS, Yang HC, Lee ST, Chen BS, Sun LY (eds.). 1985. Annotated Bibliography of Diamondback Moth. Asian Vegetable Research and Development Center, Taipei, Taiwan. 469 pp.
- Workman RB, Chalfant RB, Schuster DJ. 1980. Management of the cabbage looper and diamondback moth on cabbage by using two damage thresholds and five insecticide treatments. Journal of Economic Entomology 73: 757-758.
Author: John L. Capinera, University of Florida
Photographs: Lyle Buss, University of Florida
Web Design: Don Wasik, Jane Medley
Publication Number: EENY-119
Publication Date: January 2000. Latest Revision: December 2018.
An Equal Opportunity Institution
Featured Creatures Editor and Coordinator: Dr. Elena Rhodes, University of Florida
Phyllostachys nigra is very similar to Phyllostachys bambusoides (madake) and Phyllostachys aurea (golden bamboo), and relatively similar to Arundo donax (giant reed). These species can be distinguished by the following differences:
- P. nigra has blackish or purplish-black coloured mature stems that are usually 1-4 cm thick. These stems have a distinctive groove running lengthwise from above where the side branches are produced. Its relatively small leaf blades (up to 12 cm long) have a short stalk-like (Pseudo-petiolate) constriction at their base and sometimes a few bristles (Setae) are present near the top of the leaf sheath. Flowers are very rarely produced.
- P. bambusoides has greenish or yellowish coloured mature stems that are usually 6-20 cm thick. These stems have a distinctive groove running lengthwise from above where the side branches are produced. Its relatively small leaf blades (up to 10 cm long) have a short stalk-like (Pseudo-petiolate) constriction at their base and several black bristles (Setae) are present near the top of the leaf sheath. Flowers are very rarely produced.
- P. aurea has greenish-yellow or golden coloured mature stems that are usually 2-3 cm thick. These stems have a distinctive groove running lengthwise from above where the side branches are produced. Its relatively small leaf blades (up to 15 cm long) have a short stalk-like (Pseudo-petiolate) constriction at their base and sometimes a few bristles (Setae) are present near the top of the leaf sheath. Flowers are very rarely produced.
- A. donax has greenish coloured stems that are up to 4 cm thick. These stems are rounded and do not have any lengthwise grooves. Its very large leaves (up to 80 cm long) are not constricted at the base of the leaf blade. Flowers are regularly borne in very large, feathery, whitish coloured open panicles at the tops of the stems (Culms).
The story of fluoridation reads like a postmodern fable, and the moral is clear: a scientific discovery might seem like a boon.
The CDA was passed not in the name of censorship but in the name of protecting children from stumbling across sexual material.
And Epstein continues to steer money toward universities to advance scientific research.
Their three-day scientific outing was paid for by Epstein and was big success.
“Gronkowski” itself never manages to sound more erotic than the name of a hearty Polish stew or a D-list WWE performer.
In pursuing his alchemical researches, he discovered Prussian blue, and the animal oil which bears his name.
Elyon is the name of an ancient Phœnician god, slain by his son El, no doubt the “first-born of death” in Job xviii.
"It is ill-fated" and Alessandro blamed himself for having forgotten her only association with the name.
"Garnache," came the other's crisp, metallic voice, and the name had a sound as of an oath on his lips.
Children, and the building of a city shall establish a name, but a blameless wife shall be counted above them both.
A Tree and Its Species Classification
What does "species" of tree mean? A tree species is an individual kind of tree that shares common parts on the lowest taxonomic level. Trees of the same species have the same characteristics of bark, leaf, flower, and seed and present the same general appearance. The word species is both singular and plural.
There are nearly 1,200 tree species that grow naturally in the United States. Each tree species tends to grow together in what foresters call tree ranges and timber types, which are confined to geographic areas with similar climatic and soil conditions. Many more have been introduced from outside North America and are considered to be naturalized exotics. These trees do very well when grown in similar conditions they were native to. It is interesting that tree species in the United States far exceeds the native species of Europe.
The Scientific Method
"We also discovered that science is cool and fun because you get to do stuff that no one has ever done before." In the article Blackawton bees, published by eight to ten year old students: Biology Letters (2010) http://rsbl.royalsocietypublishing.org/content/early/2010/12/18/rsbl.2010.1056.abstract.
There are basic methods of gaining knowledge that are common to all of science. At the heart of science is the scientific investigation, which is done by following the scientific method. A scientific investigation is a plan for asking questions and testing possible answers. It generally follows the steps listed in Figure below. See http://www.youtube.com/watch?v=KZaCy5Z87FA for an overview of the scientific method.
Steps of a Scientific Investigation. A scientific investigation typically has these steps. Scientists often develop their own steps they follow in a scientific investigation. Shown here is a simplification of how a scientific investigation is done.
A scientific investigation typically begins with observations. You make observations all the time. Let&rsquos say you take a walk in the woods and observe a moth, like the one in Figure below, resting on a tree trunk. You notice that the moth has spots on its wings that look like eyes. You think the eye spots make the moth look like the face of an owl.
Figure 2: Marbled emperor moth Heniocha dyops in Botswana. (CC-SA-BY-4.0 Charlesjsharp).
Does this moth remind you of an owl?
Asking a Question
Observations often lead to questions. For example, you might ask yourself why the moth has eye spots that make it look like an owl&rsquos face. What reason might there be for this observation?
Forming a Hypothesis
The next step in a scientific investigation is forming a hypothesis. A hypothesis is a possible answer to a scientific question, but it isn&rsquot just any answer. A hypothesis must be based on scientific knowledge, and it must be logical. A hypothesis also must be falsifiable. In other words, it must be possible to make observations that would disprove the hypothesis if it really is false. Assume you know that some birds eat moths and that owls prey on other birds. From this knowledge, you reason that eye spots scare away birds that might eat the moth. This is your hypothesis.
Testing the Hypothesis
To test a hypothesis, you first need to make a prediction based on the hypothesis. A prediction is a statement that tells what will happen under certain conditions. It can be expressed in the form: If A occurs, then B will happen. Based on your hypothesis, you might make this prediction: If a moth has eye spots on its wings, then birds will avoid eating it.
Next, you must gather evidence to test your prediction. Evidence is any type of data that may either agree or disagree with a prediction, so it may either support or disprove a hypothesis. Evidence may be gathered by an experiment. Assume that you gather evidence by making more observations of moths with eye spots. Perhaps you observe that birds really do avoid eating moths with eye spots. This evidence agrees with your prediction.
Evidence that agrees with your prediction supports your hypothesis. Does such evidence prove that your hypothesis is true? No a hypothesis cannot be proven conclusively to be true. This is because you can never examine all of the possible evidence, and someday evidence might be found that disproves the hypothesis. Nonetheless, the more evidence that supports a hypothesis, the more likely the hypothesis is to be true.
The last step in a scientific investigation is communicating what you have learned with others. This is a very important step because it allows others to test your hypothesis. If other researchers get the same results as yours, they add support to the hypothesis. However, if they get different results, they may disprove the hypothesis.
When scientists share their results, they should describe their methods and point out any possible problems with the investigation. For example, while you were observing moths, perhaps your presence scared birds away. This introduces an error into your investigation. You got the results you predicted (the birds avoided the moths while you were observing them), but not for the reason you hypothesized. Other researchers might be able to think of ways to avoid this error in future studies.