It is possible that Lucy had children, but no one knows for certain. Scientists usually look for marks on the symphyseal border of the female pubis bone for signs of childbirth. These marks, called parturition scars, look like pits on the surface of the pubis. Lucy does have some pitting on her pubis. Typically, the more pits, the more children the female had. But scientists are unable to tell how many children Lucy had.

Scientists are not certain about any injuries Lucy might have had before she died. Her skeleton looks different than it did when she died because it has been crushed by sediments for millions of years and then turned into a fossil. (See also "How did Lucy die?")

There is no evidence that Lucy had a spoken language, however, she may have been able to communicate in different forms. There is documented proof that primates communicate in a variety of ways such as using gestures, facial expressions and vocalizations. Humans communicate this way, too. For example, if you see a friend smile, it is interpreted as a sign of happiness.

No! Lucy's brain size relative to body size is comparable to modern apes. Relatively brains size is simply the size of the brain relative to the rest of the body. Brain size is not necessarily a diagnostic factor of intelligence. For example, fossilized Neanderthal skulls exhibit a larger cranial capacity than modern humans, which many scientists attribute to an adaptation to a colder climate. For Lucy's species to survive for an extended period of time, (over 1 million years according to the fossil records) she must have been very smart.

After Lucy died, her bones settled into dirt and rocks. These are called sediments. She then was buried by many more layers of sediments. The weight of all these layers of sediments crushed some of her bones. After a long time, the calcium in her bone was replaced with minerals from the surrounding soils. This process is called mineralization. It turns the bone into rock and preserves it for a long time.

No one really knows how Lucy died. Her skeleton looks different than it did when she died because it has been crushed by sediments for millions of years and then turned into a fossil. (See also "Did Lucy have any injuries, such as broken bones?")

Her official name is AL 288-1, but Lucy got her famous nickname from the Beatle's song, "Lucy in the Sky with Diamonds." The people who found her were listening to this song the night she was found. Lucy was also named Dinkinesh by Johanson. In Amharic, an Ethiopian language, Dinkinesh means "you are a beautiful, unique, special one."

Lucy appears to have walked bipedally (on two legs) but also may have spent a lot of time in trees. Lucy has long arms relative to her legs. Her finger and toe bones (phalanges) are curved like those seen in tree climbing (arboreal) hominins. But her hips and legs are more like bipedal hominins, such as modern humans, and the angle of her knee (valgus) suggests she walked upright on two legs.

Lucy's pelvis bone is similar in shape to that of a modern human female, and her fossilized skeleton is very small when compared to some other A. afarensis fossils. Lucy's size suggests that she belonged to a sexually dimorphic species, a species in which the males have larger body sizes than females.

Lucy had fully erupted wisdom teeth (or third molars) and her bones appear fully fused. Bones form in separate pieces and fuse (connect) together, and teeth erupt at different times in life as an animal grows. By the age of 35, most humans have fully erupted third molars and fused bones.

Lucy was about 107 centimeters (3'6") tall. A. afarensis were sexually dimorphic, meaning that males were larger than females. A male may have been over four feet tall.

Lucy probably ate fruits, plants, roots, seeds, insects, and possibly small animals. A combination of cusps patterns and lines that are left on the surface of the tooth when an animal eats can help scientists better understand an animal's diet.

Lucy is 3.2 million years old. Scientists arrived at this date by testing chemicals, called Potassium-argon and Argon-argon, in layers of volcanic ash above and below the rock layer where Lucy was found.

No one knows what kind of family Lucy had. Nearby the Hadar site where Lucy was found, anthropologists also found a group of at least 13 different A. afarensis individuals that were living about the same time as Lucy. This may be evidence that Lucy lived in a large family-like group.

Geologists have determined that Lucy lived around a large lake surrounded by trees. This would have provided easy access to water, plants and prey animals.

Stone tools have not been found at the same sites as A. afarensis fossils. However, this does not mean Lucy did not use tools. In fact, Lucy probably used tools made of wood or reed that did not preserve over the millions of years of weathering and burial. It is also possible that she used unworked rocks and stones as tools, just as modern chimpanzees use today.

Lucy is an Australopithecus afarensis, a well documented group of early hominins. Fossil Australopithecines show evidence of bipedalism and generally have relatively small brain size and body stature. This species may be ancestral to later Australopithecus species and early Homo.

Lucy didn't live in a house like modern humans. Instead, Lucy most likely spent the night in trees or in caves.

Lucy was discovered on November 24, 1974, in the Hadar Formation in the central Afar region of Ethiopia.

Lucy was found by Donald Johanson and Tom Gray.

Lucy is the best preserved and most complete specimen of A. afarensis. About 40% of the entire skeleton was recovered. Her fossil dates to about 3.2 mya. Scientists have answered many questions about bipedal evolution by looking at the part of Lucy's skeleton below her skull, also called the postcranial skeleton.

No! All species are related to one another because they share genetic material inherited from a common ancestor, though some species are more closely related than others. For example, human and chimpanzees share over 98% of the same genetic material. Based on this fact, we can safely say humans and chimps shared a recent common ancestor that had ape-like morphology. This does not mean humans came from apes because apes have also evolved over millions of years since splitting from the last common ancestor with humans. Scientists are still debating the exact morphology of the last common ancestor. The molecular data does tell us that this ancestor may have lived between 5 and 7 million years ago. On the other hand, humans share nearly 85% of their DNA with mice. Eomaia scansoria was the last known common ancestor of both mice and humans and lived between 75 and 125 million years ago.

Both! A fact is a hypothesis that has been tested to the extent that the observed results are reliably predictable. In short, a fact is a piece of evidence. Facts may be used to define a scientific law, such as the law of gravity or the laws of motion. However, most recent scientific discoveries choose to address a set of tested hypotheses that fit together to explain an observed fact(s) as a theory, such as the germ theory of medicine or the atomic theory of matter. In modern scientific vernacular, law and theory mean the same thing.

The genetic change over time in organisms, known as biological evolution, is an observable fact which can absolutely be observed in both living organisms and in the fossil record. The "theory of evolution" refers to the evolutionary mechanisms that may affect change within a population.

An adaptation is a characteristic with a specific function that enables an organism to live in its environment and successfully reproduce. Adaptation is also a process in which organisms adjust to their environment. Selection pressure is the force that shapes specific adaptations. Adaptation is viewed as a response to problems set by the environment, and an adaptation can be morphological or behavioral.

Evolution is the process of change over time. Rocks, cars, computers, humans- everything changes over time. So when someone asks, "What is evolution?" the real question is "What is biological evolution?"

Biological evolution is descent with modification through genetic inheritance, i.e. parents pass along genetic traits to their offspring. Most importantly, biological evolution is a population process. Individuals are subject to selection and adaptation; populations evolve. Evolution may result in a new species or changes in an existing species. There are four mechanisms that act upon evolution: natural selection, random mutation, genetic drift, and gene flow. (More information on evolution can be found in the "What is Evolution?" teaching module.)

Gene flow is the transfer of genes from one population to another. Genetic diversity is a product of gene flow. The introduction or increase of new alleles (genes) into the genetic material of a population prevents populations from diverging into new species.

Genetic drift is the accidental shift in allele frequencies in a population. It is caused by random chance as some individuals in a population leave behind a few more offspring than others. Its effects are most dramatic in small populations. The founder effect, an example of genetic drift, is seen in populations derived from a small sample of individuals who do not represent the genetic variation seen in the parent population. Genetic drift does not produce adaptations.

Mutation occurs when changes are made to the genetic material. This can occur due to a copying error during DNA replication, or exposure to radiation, chemicals, or viruses. Mutation is typically random.

One of the processes that must occur for evolution to exist is natural selection. Between individuals in a species there are always variations in the genetic material. Sometimes these variations give certain individuals a better chance at survival. If these individuals leave more offspring than others, their offspring will have a better chance at survival, too. The greater number of offspring from one individual, the greater the chance of changing the genetic structure of the population. After many generations, these small changes can add up to make an obvious difference. It has been proposed that these processes can lead to adaptation and eventually a new species over time.

No. Most adult men and women have 12 pairs of ribs. However, there is variation in this number and some people may have an extra pair of ribs or an extra vertebra.

A fossil is formed when hard elements of a skeleton, such as shells, teeth and bones, are quickly buried by sand or mud. These sediments are turned into rock over millions of year. During this time the organic components of the skeleton are replaced with minerals, a process called mineralization. The transition from bone to stone forms a fossil.

A species is a group of interbreeding or potentially interbreeding organisms capable of producing fertile offspring. The process of evolution leads to new types of organisms, which may eventually be classified as a new species. All offspring inherit genetic material from their parents, though some individuals experience genetic mutation making them slightly different from their parents. New species forms when a population (i.e. daughter population), experiences genetic change due to an environmental or genetic factor, after splitting off from the ancestral (i.e. parent) population. This is commonly referred to as a speciation event.

When a population of organisms becomes more reproductively and genetically isolated, it may be labeled as a new species. In cases where the species is extinct and known only from the fossil record, scientists can classify the fossil into a species based on traits that make fossil specimens unique from one another. In more recent years, scientists have used DNA analysis to differentiate between species.

Bone is made up of both organic and inorganic components. Protein collagen provides the flexibility of bones while the mineral components of bones are mostly hydroxyapatites, formed primarily of calcium and phosphorus. Small amounts of sodium, magnesium, fluorides, and carbonates are also present. One-third of living bone is water.

Both terms are most commonly used to describe a group that includes humans and our bipedal fossil relatives. The term "hominid" reflects a classification that groups humans and their bipedal fossil relatives in the family Hominidea to the exclusion of apes who are placed in the families Hylobatidae (gibbon and siamang) and Pongidae (orangutan, chimpanzee, bonobo and gorilla).

The term "hominin" reflects a classification that groups humans and chimpanzees in the subfamily homininae and separates humans and their close fossil relatives into a separate tribe, the Hominini. Since the molecular data clearly shows a close genetic relationship between humans and chimpanzees, it is more appropriate to use the term "hominin" when discussing human evolution.