Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

By the end of this section, you will be able to:Describe the derived features that distinguish primates from other animalsExplain why scientists are having difficulty determining the true lines of descent in hominids

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"It might not be your first choice for a meal, but many mammals appear to find earth an appetizing addition to their diet Known as geophagy, scientists still aren’t sure what causes the surprisingly common urge to eat soil or clay To understand soil eating and its causes, researchers reviewed every documented case of soil eating in monkeys and apes They identified cases of soil eating in 136 species – over half of all monkeys and apes found around the globe – suggesting the behavior is more common than previously thought Evidence from the 287 articles reviewed also suggests that geophagy is a form of self-medication Geophagy may provide protection against disease-causing pathogens and supplement essential nutrients Although more research is needed, the work lays a foundation for future investigations into the causes and health impacts of geophagy The findings could also reveal new ways to promote the health of both wild and captive primate populations Pebsworth PA, et al..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Chronic diarrhea is a messy disease that can even be fatal. In addition to being widespread in humans, it’s common in captive rhesus macaques, which are important research animals. However, the causes of chronic diarrhea are often murky. To learn more, researchers recently compared the gut microbiomes of rhesus macaques with and without chronic diarrhea. According to metagenomic sequencing, sick macaques had significant depletion of Lactobacillus bacteria but increased abundance of opportunistic pathogens and bacteria that degrade the protective intestinal mucus layer. Metabolic pathways related to virulence factor synthesis were also activated in macaques with diarrhea, whereas beneficial short-chain fatty acid pathways were enhanced in asymptomatic macaques. In addition, compared with those of asymptomatic macaques, the gut bacteria of sick macaques had higher expression of antibiotic resistance genes (ARGs) and greater resistance to most tested antibiotics..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"The abundant vegetation in forested areas can obstruct the view of potential food sources giving animals that can locate food with senses other than sight an advantage. While researchers hypothesize that fruit aromas evolved to attract primates to effectively disperse the seeds they contain, it’s unclear whether primates can use odor cues to locate fruit outside of their visual range. A recent study tested whether ring-tailed lemurs could detect distant hidden fruit by scent alone. The researchers hid containers holding real and imitation cantaloupe 4-17 m away from a trail routinely used by lemurs. They found that the lemurs were able to locate the real cantaloupe when the wind blew its scent toward the trail but were unable to find the imitation cantaloupe. The lemurs also showed behaviors indicating that they were following the cantaloupe “odor plume..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"HIV affects 38 million people worldwide, and a cure remains elusive. One important factor in transmission and pathogenesis lies outside the virus: the microbiome of the gut and genital surfaces is increasingly recognized as a key player during HIV infection, affecting inflammation and microbial translocation. In an effort to better understand the effects of microbes on health during infection, researchers turned to an animal model. Vervet monkeys are a natural host for a closely related virus, simian immunodeficiency virus (SIV). Because they have faced SIV for hundreds of thousands of years, the monkeys have co-evolved with the virus, allowing vervets to have nonprogressive SIV infection. By evaluating the microbiota of SIV-infected vervets, the researchers sought to determine what microbe-associated factors protected vervets against AIDS. Characterization of fecal, rectal, vaginal, and penile microbiomes in vervets from heavily SIV-infected areas in South Africa..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Housemates, science shows, share more than just space. The types of microbes that colonize the gut tend to be similar among members of the same family or household. But where does the sharing begin: through contact, environment, or diet? And do more social factors like status play a role? To find out, researchers recently examined the microbiomes of seven neighboring groups of wild Verreaux’s sifakas in Madagascar. Sifakas in the same group tended to have more similar microbiomes, but differences between groups weren’t explained by differences in diet, home range, or habitat. Maternal lineage was an important driver of similarity within groups and may also explain why adult group members, which are generally less related, shared the least similar gut microbiota. In addition, dominant males had different microbiomes than their group-mates, possibly because of rank-related differences in physiology and scent-marking behaviors..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Much recent research points toward a strong link between the microorganisms living in the gut and human health. Changes in this microbial community as a person grows older are thought to stem from changes in lifestyle and wellbeing associated with modern society, but evidence to support this claim is lacking. To gain a better understanding of how age affects the gut microbial community under natural conditions, researchers looked toward wild macaques. Using gene sequencing techniques, they found that the gut bacterial composition of individual macaques exhibited a unique personal signature and that this signature became increasingly unstable with age. This instability was linked to an increase in the relative abundance of rare bacterial groups. The uniqueness of an individual’s gut microbiota also increased with age, potentially due in part to a decrease in social interaction..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.