Thursday Lecture – Origin of Agriculture, continued

Thursday Lecture – Origin of Agriculture, continued
- Geographical origin of plant crops - Changes under domestication Our discussion of the origin of agriculture continues with further discussion of the geographical origin of plant crops, and we will also talk about changes that occur in crops when they are domesticated.

Assignment #3 Due Date: Tuesday 2/1
List 5 plant foods that you have consumed this week (they may be foods that consist entirely of the plant; or foods that contain the plant as one of the ingredients). Prepare a one page world map that is labeled to show where each plant food originated (use Table 2.1 of your textbook as your source of information) Due Date: Tuesday 2/1 Can Be Returned as Hard Copy or File Attachment to message

Briefly explain the myth regarding Persephone, Demeter, Pluto and the pomegranate. How does it relate to agriculture? Where and when did agriculture begin? Who was Nikolai Vavilov?

Geological Time Scale To put our discussions regarding the timing of the origin of agriculture in perspective we can review briefly the history of our planet using a standard geological time scale. Geologists have divided up intervals of our planet’s history into major subdivisions, including eons, eras and periods. Note that these had begun to be named and delimited based on studies of stratigraphy and paleontology before we had any way to provide absolute dates. The climate of the earth and the position of continents have changed significantly over time. The point of this slide is to emphasize that agriculture is a very recent innovation.

Where did agriculture originate?
4-5+ Centers North America Near East Mexico Southeast Asia South America North America was not listed by early researchers such as Vavilov as a center, but archaeological evidence shows that a number of distinctive crops were in cultivation – and probably domesticated – prior to the arrival of corn and beans from the nearby Mexican region. Of these, only sunflower remains today as an important world agricultural crop. Sub-sahara Africa

What types of plants were utilized in early agriculture?
Cereals – Members of the Grass Family Poaceae Near East: Far East: Subsaharan Africa: Early agricultural systems were all based on a similar suite of types of crop plants, although the exact species that were cultivated varied from one region to another. All early agricultural systems included one or more cereal crops (members of the grass family Poaceae) and one or more legume crops (members of the bean family Fabaceae). The combination of cereal + legume provides a diet that meets the needs of humans for all of the necessary amino acids to make proteins. In addition, many early agricultural systems utilized one or more starchy staples as a source of calories. The cereals utilized in the Near East region included barley and wheat. In the Far East, rice was the major cereal crop. It has distinctive needs for cultivation that may also have helped to shape societies in this region. In the New World, the crop that we call corn in America (but that is called maize in most of the English speaking world) was the staple cereal. Corn cultivation spread early to South America. Mexico South America

Cereals Near East: Barley, Wheat Far East: Rice Subsaharan Africa: Millets Early agricultural systems were all based on a similar suite of types of crop plants, although the exact species that were cultivated varied from one region to another. All early agricultural systems included one or more cereal crops (members of the grass family Poaceae) and one or more legume crops (members of the bean family Fabaceae). The combination of cereal + legume provides a diet that meets the needs of humans for all of the necessary amino acids to make proteins. In addition, many early agricultural systems utilized one or more starchy staples as a source of calories. The cereals utilized in the Near East region included barley and wheat. In the Far East, rice was the major cereal crop. It has distinctive needs for cultivation that may also have helped to shape societies in this region. In the New World, the crop that we call corn in America (but that is called maize in most of the English speaking world) was the staple cereal. Corn cultivation spread early to South America. Mexico Corn South America Acquired Corn

Legumes – members of pea family Fabaceae Near East: Far East: Subsaharan Africa: Each early center of agriculture also include one or more legumes - members of the bean family Fabaceae. Although cereals and legumes can be sources of proteins, the quality of the protein in each is not satisfactory for human nutritional needs - each is low in one or more amino acids that is essential for humans. The combination of cereal + legume provides a complete set of necessary amino acids. Mexico South America

Legumes Near East: Peas, Lentils Far East: Soybeans, Mung Bean Subsaharan Africa: Cowpeas (black-eyed peas); Vetch Each early center of agriculture also include one or more legumes - members of the bean family Fabaceae. Although cereals and legumes can be sources of proteins, the quality of the protein in each is not satisfactory for human nutritional needs - each is low in one or more amino acids that is essential for humans. The combination of cereal + legume provides a complete set of necessary amino acids. Mexico Common Bean South America Common Bean, Lima Bean, Peanut

Starchy Staples – members of various families Near East: Far East: Subsaharan Africa: Crops that produce high amounts of starch, and thus provide a rich source of calories, were also utilized in all of the tropical areas where agriculture originated. Mexico South America

Starchy Staples Near East: Dates Far East: Banana, Taro, Breadfruit Subsaharan Africa: Yams Crops that produce high amounts of starch, and thus provide a rich source of calories, were also utilized in all of the tropical areas where agriculture originated. Mexico Sweet Potato South America Potatoes, Manioc

Did agriculture have a single origin?
Criteria to evaluate: crops utilized methods of cultivation temporal considerations The issue of whether agriculture originated only once, and then was carried about the world by people (cultural diffusion), or was discovered independently in several different places (independent invention) has been a topic of discussion for botanists and anthopologists. The emerging view that agriculture originated gradually and over a prolonged period may render this question less pressing.

Criteria to evaluate: crops utilized methods of cultivation temporal considerations Hypothesis 1: idea of agriculture so distinctive that it probably originated just once - humans carried it around the world, e.g. on long oceanic voyages (not recorded historically) a la Thor Heyerdahl The issue of whether agriculture originated only once, and then was carried about the world by people (cultural diffusion), or was discovered independently in several different places (independent invention) has been a topic of discussion for botanists and anthopologists. The emerging view that agriculture originated gradually and over a prolonged period may render this question less pressing.

Criteria to evaluate: crops utilized methods of cultivation temporal considerations Hypothesis 1: idea of agriculture so distinctive that it probably originated just once - humans carried it around the world, e.g. on long oceanic voyages (not recorded historically) a la Thor Heyerdahl Hypothesis 2: differences in plants and methods of cultivation  most likely that agriculture was invented independently in different areas The issue of whether agriculture originated only once, and then was carried about the world by people (cultural diffusion), or was discovered independently in several different places (independent invention) has been a topic of discussion for botanists and anthopologists. The emerging view that agriculture originated gradually and over a prolonged period may render this question less pressing.

Alternative Views – Origin of Agriculture
“Classical View” – sudden, dramatic event; requires explanation raises issue of single vs. multiple origins New View (Box 2.1, text) – gradual transition issue of origin less significant Major Points: Once adopted, agriculture stayed with culture Agriculture adopted in various parts of the world, with differing sets of plants In the view that is now emerging through careful and comprehensive studies of relevant artefacts coupled with better and more accurate methods of dating, the emergence of agriculture appears to be more gradual, and the result of multiple advances over relatively widespread areas rather than a single dramatic discovery at one location. Nevertheless, it can be noted that before about 10,000 years ago there were no societies that relied solely on agriculture. There are no known cases of a society reverting to the hunter-gathering approach after adoption of agriculture. Further, agriculture was adopted – most likely independently – in various areas of the world. This has led scientists to try to identify the critical factors that would push a society past the “point of no return” and move beyond horticulture to agriculture.

What are the consequences for people of origin of agriculture?
Cities Agriculture appears to have had profound effects on human civilizations. Although it is often difficult to tease apart cause and effect, a number of innovations appear to be directly related to agriculture: these include the rise of cities, made possible by the increased food production; the development of writing, to keep track of harvests and of trade; and increases in population size. Note, however, that agriculture did not eliminate hunger. In fact, some would argue that agriculture has had a net detrimental effect on humans.

Cities Civilization, associated with need to keep track of events (possibly stimulated development of writing) Agriculture appears to have had profound effects on human civilizations. Although it is often difficult to tease apart cause and effect, a number of innovations appear to be directly related to agriculture: these include the rise of cities, made possible by the increased food production; the development of writing, to keep track of harvests and of trade; and increases in population size. Note, however, that agriculture did not eliminate hunger. In fact, some would argue that agriculture has had a net detrimental effect on humans.

Cities Civilization, associated with need to keep track of events (possibly stimulated development of writing) increased population size Agriculture appears to have had profound effects on human civilizations. Although it is often difficult to tease apart cause and effect, a number of innovations appear to be directly related to agriculture: these include the rise of cities, made possible by the increased food production; the development of writing, to keep track of harvests and of trade; and increases in population size. Note, however, that agriculture did not eliminate hunger. In fact, some would argue that agriculture has had a net detrimental effect on humans.

Cities Civilization, associated with need to keep track of events (possibly stimulated development of writing) increased population size did not eliminate hunger Agriculture appears to have had profound effects on human civilizations. Although it is often difficult to tease apart cause and effect, a number of innovations appear to be directly related to agriculture: these include the rise of cities, made possible by the increased food production; the development of writing, to keep track of harvests and of trade; and increases in population size. Note, however, that agriculture did not eliminate hunger. In fact, some would argue that agriculture has had a net detrimental effect on humans.

Nikolai Vavilov – Scientific Contributions
Russian/Soviet scientist ( ) Institutional Leader – “All Union Institute of Plant Industry”: The Russian scientist Nikolai Vavilov made seminal contributions to our understanding of the origins of agriculture, including recognition of major centers and of processes involved in plant domestication. Vavilov was a brilliant and hard-working scientist who made numerous contributions during his career. He rose to a high leadership position in the Soviet agricultural system and produced books and papers with influential new ideas. Unfortunately, his career came to a sad end associated with the tumultuous events that affected Russia during the middle of he 20th century.

Russian/Soviet scientist ( ) Institutional Leader – “All Union Institute of Plant Industry”: staff of 20,000 in 400 research laboratories; 160,000 plant/seed samples The Russian scientist Nikolai Vavilov made seminal contributions to our understanding of the origins of agriculture, including recognition of major centers and of processes involved in plant domestication. Vavilov was a brilliant and hard-working scientist who made numerous contributions during his career. He rose to a high leadership position in the Soviet agricultural system and produced books and papers with influential new ideas. Unfortunately, his career came to a sad end associated with the tumultuous events that affected Russia during the middle of he 20th century.

Russian/Soviet scientist ( ) Institutional Leader – “All Union Institute of Plant Industry”: staff of 20,000 in 400 research laboratories; 160,000 plant/seed samples “Centers of Origin of Cultivated Plants” (Book ) Novel approach to biogeography – center of diversity = center of origin The Russian scientist Nikolai Vavilov made seminal contributions to our understanding of the origins of agriculture, including recognition of major centers and of processes involved in plant domestication. Vavilov was a brilliant and hard-working scientist who made numerous contributions during his career. He rose to a high leadership position in the Soviet agricultural system and produced books and papers with influential new ideas. Unfortunately, his career came to a sad end associated with the tumultuous events that affected Russia during the middle of he 20th century.

Russian/Soviet scientist ( ) Institutional Leader – “All Union Institute of Plant Industry”: staff of 20,000 in 400 research laboratories; 160,000 plant/seed samples “Centers of Origin of Cultivated Plants” (Book ) Novel approach to biogeography – center of diversity = center of origin Law of Homologous Series of Variation (paper ) The Russian scientist Nikolai Vavilov made seminal contributions to our understanding of the origins of agriculture, including recognition of major centers and of processes involved in plant domestication. Vavilov was a brilliant and hard-working scientist who made numerous contributions during his career. He rose to a high leadership position in the Soviet agricultural system and produced books and papers with influential new ideas. Unfortunately, his career came to a sad end associated with the tumultuous events that affected Russia during the middle of he 20th century.

The Lysenko Affair T. D. Lysenko – Russian/Soviet Plant Breeder ( ) The story of the career of Vavilov provides a cautionary tale about the mixing of politics with science. Another Russian scientist, T. D. Lysenko, started his career working under Vavilov, who helped and encouraged him early in his career. Lysenko was involved with a phenomenon called vernalization which was helpful in the production of crops in areas of short growing seasons. As he rose in prominence, he tried to extend the implications of his early successes into all areas of crop production. His ideas found favor in the Soviet government, in part because certain implications of Darwinian evolution did not fit with Marxist-Leninist concepts. The Lamarckian concepts, particularly that changes to an individual could be inherited by its offspring, were more compatible to Marxist thinking. As Lysenko ascended in power, he fell into the temptation of making his results fit his theories, and suppressed the work of those whose ideas did not fit with his own.

The Lysenko Affair T. D. Lysenko – Russian/Soviet Plant Breeder ( ) - Discovery of “vernalization” (induction of early flowering in biennial crops through use of cold treatment) The story of the career of Vavilov provides a cautionary tale about the mixing of politics with science. Another Russian scientist, T. D. Lysenko, started his career working under Vavilov, who helped and encouraged him early in his career. Lysenko was involved with a phenomenon called vernalization which was helpful in the production of crops in areas of short growing seasons. As he rose in prominence, he tried to extend the implications of his early successes into all areas of crop production. His ideas found favor in the Soviet government, in part because certain implications of Darwinian evolution did not fit with Marxist-Leninist concepts. The Lamarckian concepts, particularly that changes to an individual could be inherited by its offspring, were more compatible to Marxist thinking. As Lysenko ascended in power, he fell into the temptation of making his results fit his theories, and suppressed the work of those whose ideas did not fit with his own.

The Lysenko Affair T. D. Lysenko – Russian/Soviet Plant Breeder ( ) - Discovery of “vernalization” (induction of early flowering in biennial crops through use of cold treatment) - Renunciation of “Darwinian Evolution” in favor of a Lamarckian-type explanation The story of the career of Vavilov provides a cautionary tale about the mixing of politics with science. Another Russian scientist, T. D. Lysenko, started his career working under Vavilov, who helped and encouraged him early in his career. Lysenko was involved with a phenomenon called vernalization which was helpful in the production of crops in areas of short growing seasons. As he rose in prominence, he tried to extend the implications of his early successes into all areas of crop production. His ideas found favor in the Soviet government, in part because certain implications of Darwinian evolution did not fit with Marxist-Leninist concepts. The Lamarckian concepts, particularly that changes to an individual could be inherited by its offspring, were more compatible to Marxist thinking. As Lysenko ascended in power, he fell into the temptation of making his results fit his theories, and suppressed the work of those whose ideas did not fit with his own.

The Lysenko Affair T. D. Lysenko – Russian/Soviet Plant Breeder ( ) - Discovery of “vernalization” (induction of early flowering in biennial crops through use of cold treatment) - Renunciation of “Darwinian Evolution” in favor of a Lamarckian-type explanation Ascension to political power (“dictator of science” under Stalin); misuse of science to support socio-political philosophy The story of the career of Vavilov provides a cautionary tale about the mixing of politics with science. Another Russian scientist, T. D. Lysenko, started his career working under Vavilov, who helped and encouraged him early in his career. Lysenko was involved with a phenomenon called vernalization which was helpful in the production of crops in areas of short growing seasons. As he rose in prominence, he tried to extend the implications of his early successes into all areas of crop production. His ideas found favor in the Soviet government, in part because certain implications of Darwinian evolution did not fit with Marxist-Leninist concepts. The Lamarckian concepts, particularly that changes to an individual could be inherited by its offspring, were more compatible to Marxist thinking. As Lysenko ascended in power, he fell into the temptation of making his results fit his theories, and suppressed the work of those whose ideas did not fit with his own.

The Lysenko Affair T. D. Lysenko – Russian/Soviet Plant Breeder ( ) - Discovery of “vernalization” (induction of early flowering in biennial crops through use of cold treatment) - Renunciation of “Darwinian Evolution” in favor of a Lamarckian-type explanation Ascension to political power (“dictator of science” under Stalin); misuse of science to support socio-political philosophy Falsification of experimental results Suppression of science/scientists The story of the career of Vavilov provides a cautionary tale about the mixing of politics with science. Another Russian scientist, T. D. Lysenko, started his career working under Vavilov, who helped and encouraged him early in his career. Lysenko was involved with a phenomenon called vernalization which was helpful in the production of crops in areas of short growing seasons. As he rose in prominence, he tried to extend the implications of his early successes into all areas of crop production. His ideas found favor in the Soviet government, in part because certain implications of Darwinian evolution did not fit with Marxist-Leninist concepts. The Lamarckian concepts, particularly that changes to an individual could be inherited by its offspring, were more compatible to Marxist thinking. As Lysenko ascended in power, he fell into the temptation of making his results fit his theories, and suppressed the work of those whose ideas did not fit with his own.

Vavilov vs. Lysenko Vavilov broadly trained scientist Lysenko
narrowly trained agronomist Vavilov was most prominent among the many victims of Lysenko. Because he did not embrace the “pseudoscience” of Lysenko, Vavilov was arrested and imprisoned. He died in the harsh prison conditions during World War II. Lysenko caused immense damage to Soviet agriculture through his rejection of sound scientific principles for crop breeding and development. His own career came to an end during the post-Stalinist period.

Vavilov vs. Lysenko Vavilov broadly trained scientist
spoke/read 12 languages Lysenko narrowly trained agronomist spoke/read Russian only Vavilov was most prominent among the many victims of Lysenko. Because he did not embrace the “pseudoscience” of Lysenko, Vavilov was arrested and imprisoned. He died in the harsh prison conditions during World War II. Lysenko caused immense damage to Soviet agriculture through his rejection of sound scientific principles for crop breeding and development. His own career came to an end during the post-Stalinist period.

spoke/read 12 languages traveled around world Lysenko narrowly trained agronomist spoke/read Russian only never left Russia Vavilov was most prominent among the many victims of Lysenko. Because he did not embrace the “pseudoscience” of Lysenko, Vavilov was arrested and imprisoned. He died in the harsh prison conditions during World War II. Lysenko caused immense damage to Soviet agriculture through his rejection of sound scientific principles for crop breeding and development. His own career came to an end during the post-Stalinist period.

spoke/read 12 languages traveled around world embraced and added to scientific advances, including Mendelian genetics and Darwinian evolution Lysenko narrowly trained agronomist spoke/read Russian only never left Russia rejected scientific advances, especially Mendelian genetics and Darwinian evolution Vavilov was most prominent among the many victims of Lysenko. Because he did not embrace the “pseudoscience” of Lysenko, Vavilov was arrested and imprisoned. He died in the harsh prison conditions during World War II. Lysenko caused immense damage to Soviet agriculture through his rejection of sound scientific principles for crop breeding and development. His own career came to an end during the post-Stalinist period.

spoke/read 12 languages traveled around world embraced and added to scientific advances, including Mendelian genetics and Darwinian evolution major contributions to agriculture in Russia Lysenko narrowly trained agronomist spoke/read Russian only never left Russia rejected scientific advances, especially Mendelian genetics and Darwinian evolution inadvertantly damaged Russian agricultural system through poor policies Vavilov was most prominent among the many victims of Lysenko. Because he did not embrace the “pseudoscience” of Lysenko, Vavilov was arrested and imprisoned. He died in the harsh prison conditions during World War II. Lysenko caused immense damage to Soviet agriculture through his rejection of sound scientific principles for crop breeding and development. His own career came to an end during the post-Stalinist period.

spoke/read 12 languages traveled around world embraced and added to scientific advances, including Mendelian genetics and Darwinian evolution major contributions to agriculture in Russia died in prison, 1943 Lysenko narrowly trained agronomist spoke/read Russian only never left Russia rejected scientific advances, especially Mendelian genetics and Darwinian evolution inadvertantly damaged Russian agricultural system through poor policies forced out in 1950s Vavilov was most prominent among the many victims of Lysenko. Because he did not embrace the “pseudoscience” of Lysenko, Vavilov was arrested and imprisoned. He died in the harsh prison conditions during World War II. Lysenko caused immense damage to Soviet agriculture through his rejection of sound scientific principles for crop breeding and development. His own career came to an end during the post-Stalinist period.

Changes under Domestication
“Law of Homologous Series” –> similar changes in different species Among the contributions of Vavilov was his “Law of Homologous Series”, in which he noted that similar sets of changes can be observed in different crop plants. Some of these involve common traits that occur widely when a plant species is domesticated.

larger size of organs being utilized (fruits, seeds) Among the contributions of Vavilov was his “Law of Homologous Series”, in which he noted that similar sets of changes can be observed in different crop plants. Some of these involve common traits that occur widely when a plant species is domesticated.

larger size of organs being utilized (fruits, seeds) loss of natural means of dispersal Among the contributions of Vavilov was his “Law of Homologous Series”, in which he noted that similar sets of changes can be observed in different crop plants. Some of these involve common traits that occur widely when a plant species is domesticated.

larger size of organs being utilized (fruits, seeds) loss of natural means of dispersal loss of delayed and irregular germination of seeds Among the contributions of Vavilov was his “Law of Homologous Series”, in which he noted that similar sets of changes can be observed in different crop plants. Some of these involve common traits that occur widely when a plant species is domesticated.

larger size of organs being utilized (fruits, seeds) loss of natural means of dispersal loss of delayed and irregular germination of seeds simultaneous ripening Among the contributions of Vavilov was his “Law of Homologous Series”, in which he noted that similar sets of changes can be observed in different crop plants. Some of these involve common traits that occur widely when a plant species is domesticated.

larger size of organs being utilized (fruits, seeds) loss of natural means of dispersal loss of delayed and irregular germination of seeds simultaneous ripening loss of toxic or bitter substances Among the contributions of Vavilov was his “Law of Homologous Series”, in which he noted that similar sets of changes can be observed in different crop plants. Some of these involve common traits that occur widely when a plant species is domesticated.

larger size of organs being utilized (fruits, seeds) loss of natural means of dispersal loss of delayed and irregular germination of seeds simultaneous ripening loss of toxic or bitter substances Among the contributions of Vavilov was his “Law of Homologous Series”, in which he noted that similar sets of changes can be observed in different crop plants. Some of these involve common traits that occur widely when a plant species is domesticated. loss of mechanical means of protection

larger size of organs being utilized (fruits, seeds) loss of natural means of dispersal loss of delayed and irregular germination of seeds simultaneous ripening loss of toxic or bitter substances Among the contributions of Vavilov was his “Law of Homologous Series”, in which he noted that similar sets of changes can be observed in different crop plants. Some of these involve common traits that occur widely when a plant species is domesticated. loss of mechanical means of protection change in color of fruits and seeds

What is a Fruit? Fruit = mature ovary (for a botanist)
The technical meaning of the term “fruit” is a mature ovary. We have a variety of colloquial terms that can be used at times for what a botanist would call a fruit.

What is a Fruit, continued
Fruit = mature ovary (for a botanist) Fruits are Fruits The technical meaning of the term “fruit” is a mature ovary. We have a variety of colloquial terms that can be used at times for what a botanist would call a fruit.

Fruit = mature ovary (for a botanist) Fruits are Fruits Nuts are Fruits The technical meaning of the term “fruit” is a mature ovary. We have a variety of colloquial terms that can be used at times for what a botanist would call a fruit.

Fruit = mature ovary (for a botanist) Fruits are Fruits Nuts are Fruits Grains are Fruits The technical meaning of the term “fruit” is a mature ovary. We have a variety of colloquial terms that can be used at times for what a botanist would call a fruit.

Fruit = mature ovary (for a botanist) Fruits are Fruits Nuts are Fruits Grains are Fruits Some Vegetables are Fruits The technical meaning of the term “fruit” is a mature ovary. We have a variety of colloquial terms that can be used at times for what a botanist would call a fruit.

Fruit = mature ovary (for a botanist) Fruits are Fruits Nuts are Fruits Grains are Fruits Some Vegetables are Fruits Some Botanists are Nuts? The technical meaning of the term “fruit” is a mature ovary. We have a variety of colloquial terms that can be used at times for what a botanist would call a fruit.

Vegetable Fruits and Meaty Nuts
In this lecture, we will make a survey of selected plants, the fruit of which is used as food. The placement of these foods on the familiar USDA Nutrition Pyramid helps to illustrate the contrast between botanical and colloquial uses of the term “fruit”. The grains that are used to make bread products are the 1-seeded fruits of the grass family (Poaceae). So fruits are found in 4 of the 6 major food groups recognized by USDA. Members of the Fruit Group are all botanical fruits. Some, but not all, vegetables are also fruits – examples include tomatoes, squash, and beans. Nuts, which are placed in the meat group are typically either fruits, or the seeds of fruits.

Flowers to Fruits The ovary is the part of the flower that contains the ovules. If the ovules are fertilized, they will develop into seeds as the ovary matures into a fruit.

Flowers to Fruits Ovary (in flower) With ovule
The ovary is the part of the flower that contains the ovules. If the ovules are fertilized, they will develop into seeds as the ovary matures into a fruit.

Flowers to Fruits Ovary (in flower) With ovules

Flowers to Fruits Fruit (with 1 seed ) Ovary (in flower) With ovules

Flowers to Fruits Fruit (with 1+ seeds) Ovary (in flower) With ovules

Fruit Types Major Distinctions: dry vs. fleshy
dehiscent vs. indehiscent product of 1 ovary vs. 2+ ovaries product of 1 flower vs. multiple flowers See Table 3.1, p. 54 Also Fig. 3.1, 3.2, 3.3 pages 56-57 People classify things, and fruits are no exception. The designation of fruit types is based on a number of contrasts, including whether or not a fruit loses most of its water when mature, whether or not it has a regular mechanism to split open and release the seeds, and how many ovaries make up the fruit and where they are derived. A summary of the major types and how they differ is provided in text Table 3.1. Pericarp – fruit wall endocarp (inside) mesocarp (middle) exocarp (outside)

Dry, Indehiscent Fruits – Achene, Grain
Achene – 1-seeded, fruit and seed wall separate Chapter 5 Grain – 1-seeded, fruit and seed wall fused Fruits that have 1 seed do not need to split open to release the seed. Achenes and grains are similar, but differ in whether the fruit and seed wall remain separate or become fused to one another. There are many important crop plants that exhibit one or the other of these fruit types.

Dry Indehiscent Fruits - Nut
Nut – 1 seeded, enclosed by hard pericarp, surrounded by “husk” Nuts are also 1-seeded, but they develop a very thick fruit wall that surrounds the seed. See Figs. 3.15, 3.16, pages 70-71

Dry, Dehiscent Fruits – Follicle
Follicle – from simple ovary, splits along 1 seam only See Figs. 3.4, p. 58 Follicles split open along exactly 1 seam at maturity to release the multiple seed. There are not many follicles that we would use as a source of food. Spiraea Fruits milkweed

Dry, Dehiscent Fruits - Legume
Legume – from simple ovary, splits along 2 seams In contrast to follicles, legumes split open along two seams. Also in contrast to follicles, many legumes are very important food plants. Chapter 6 Fruit of Fabaceae, only: beans, peas, lentils etc.

Fleshy Fruits from 1 Ovary - Berry
Berry – multiple seeds, embedded in fleshy pulp Special types of Berries Pome – most of flesh = hypanthium Hesperidium – flesh = juice-filled hairs Pepo – hard rind One type of fleshy fruit is a berry - this is defined as a fruit with multiple seeds that are embedded in the fleshy pulp. Such commonly consumed fruits as tomatoes, blueberries, grapes, and bananas are examples of berries. Some berries have special traits and may be designated by a more specific term, such as the pepo, hesperidium, and pome.

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