How reasoning and evidence are used to understand human evolution.
Genetic evidence shows that humans evolved in Africa and continue to evolve.
Stone tools are well-preserved evidence of past human activity.
The hominid fossil record of the past six million years gives us surprising insights into the path of human evolution.
How humans perceive bitter taste, and the evolution of taste perception.
Second discussion in the 2011 Holiday Lectures on human evolution, on how to effectively report scientific results to the general public.
How Darwin came to publish The Origin of Species, and examples of how quickly evolution can change a population.
Comparing the artificial selection of dogs and corn with the natural selection of the stickleback fish.
The genetic mechanisms by which evolution occurs, and an overview of the evidence for evolutionary theory.
How and why butterflies and fruit flies got their spots, and the fossil record for human evolution.
A discussion on reconciling religion and science with students, the lecturers, and guest speakers.
Leading evolution educator Ken Miller discusses the controversy surrounding the teaching of evolution.
Learn about research aimed at thwarting dengue fever in the lab and in communities.
New technologies like the Virochip harness DNA's properties to identify and fight new viruses.
Understanding the immune response is essential to developing safe vaccines for dengue and other diseases.
The SARS epidemic was successfully halted by a global research effort to identify a new virus.
This discussion from the 2010 Holiday Lectures on Science explores the ethics of genetically-modified organisms and other topics.
The genesis of AIDS, identifying HIV as the virus that causes AIDS, and the modern global epidemic.
The HIV life cycle, and how the virus destroys the immune system's ability to respond to infection.
Treating HIV infection with antiretroviral therapy, and HIV's ability to develop drug resistance.
The search for an effective HIV vaccine, and advances in genomics that may lead to a breakthrough.
A discussion with three students who are helping in the global fight against HIV and AIDS.
Three HIV-positive individuals share their personal experiences about living with HIV.
Dr. Donald Ganem describes how epidemiologists, physicians, and microbiologists work together to identify and study pathogens.
Dr. Brett Finlay explains why bacterial diseases continue to be a major health problem worldwide, causing a third of the world's deaths every year.
Dr. Finlay showcases three types of bacteria to illustrate how molecular biology is allowing researchers to probe the molecular workings of bacterial infections.
Dr. Ganem analyses the complex causes of epidemics—how changes in the environment and in human social behavior can give rise to new infectious diseases.
Venomous carniverous cone snails are a rich source of molecules for scientific research and potential drug development.
Bacteria are capable of communicating and coordinating their activities with a molecular signaling system called quorum sensing.
Cone snails have evolved many different toxins for different uses. Total molecular biodiversity may number in the millions.
The quorum sensing system is a target for a new class of drugs that interfere with virulence without killing bacteria.
A discussion on biodiversity, endangered habitats, and how best to preserve the Earth's ecosystems, presented by the lecturers along with Dr. E.O. Wilson and Dr. Eric Chivian.
In this 13-minute Q&A session, Dr. Bonnie Bassler answers questions on quorum sensing and other topics related to bacteria.
In this ten-minute Q&A session, Dr. Olivera answers questions on cone snail behavior, venoms, and biodiversity.
The history of localization of function in the brain, and research that led to the understanding of localization of memory.
How a nerve cell gets its identity, sends axons, and makes connections with other cells.
Understanding the neural circuits in the spinal cord that control movement.
The cellular and molecular nature of learning and memory, investigated in simpler sea slugs and more-complex mice.
The lecturers, joined by Dr. Kay Jamison of the Johns Hopkins University School of Medicine and Dr. Gerald Fischbach of the Simons Foundation, answer questions concerning autism, manic depression, and other mental illnesses.
Although there are numerous kinds of cancer, all stem from alterations that allow cell division to outstrip cell demise.
The identification of hundreds of genes involved in the formation and spread of cancer is leading to promising new methods for diagnosis, prevention, and treatment.
Mutations in key genes can lay waste to the nervous system. By studying large families predisposed to developing these genetic disorders, scientists can identify the responsible altered gene.
Girls with Rett syndrome develop normally for about 18 months and then begin to regress. With the help of affected girls and their families, Dr. Zoghbi and her collaborators searched for the gene responsible for this neurological disorder.
Genetic research benefits health, but also raises thorny ethical issues.
Dr. Hudspeth will begin by discussing how simple organisms—such as bacteria—have the capacity to detect and react to a stimulus.
Dr. Nathans will discuss how the visual process involves the detection of light by photo-receptors in the retina.
Dr. Hudspeth will explain the basis for the ear’s remarkable ability to detect sound through the hair cell, the sensory receptor found in the inner ear.
Dr. Nathans will complete the lecture series by clarifying what is known about the brain’s ability to process and integrate various elements of the visual system, such as color, motion, and depth.
An overview of embryonic development, the progressive differentiation of cells, and properties of embryonic stem cells.
The role of stem cells in regeneration, and ongoing research to improve mammalian regeneration potency.
In cloning, a cell's genetic machinery is reprogrammed. Can we similarly coax stem cells to become specific cell types?
Finding factors to reverse age-related loss of cell maintenance, and some examples of stem cell therapies.
A discussion on policies and ethical issues associated with stem cell research.
Dr. Friedman introduces the genes and circuits that control appetite, including the key role of leptin.
Dr. Evans describes how fat communicates with muscle and how diet and exercise influence that relationship.
Dr. Evans reviews how PPARs regulate body weight by controlling whether fat is burned or stored.
Dr. Friedman shows how leptin rewires neural circuits, and how population studies may identify obesity genes.
A Q&A session on obesity and related issues, with the lecturers and students attending the Holiday Lectures on Science.
To understand life's processes, perturb them. How a process responds to an insult can provide clues about normal function or mimic a specific disease state.
Dr. Lander explores human genetic variation and how it may affect individual susceptibility to certain diseases.
Scientists now have the ability to create millions of new molecules. How do they test whether any of these molecules are useful?
A wide-ranging 45-minute discussion between Dr. Eric Lander, Dr. Stuart Schreiber, and four Washington DC-area high school teachers.
Is it a boy or a girl? Dr. David Page looks at how we define male and female and summarizes the development of human sex characteristics.
Dr. Barbara Meyer explains the value of studying model organisms and introduces the nematode C. elegans.
Having too many chromosomes can lead to too much gene expression. Dr. Meyer explains how the gene that controls dosage compensation in C. elegans works.
Dr. Page explains how successive inversions and deletions of the Y chromosome during mammalian evolution have reduced it to its present form—small and sparsely populated with genes.
Dr. Joseph Takahashi takes us on an exciting journey into a very special region of the brain—the biological clock that governs our physiology and certain behaviors.
Although tiny in size, the fruit fly has had a major impact on our understanding of circadian rhythms.
Dr. Rosbash discloses how scientists have persuaded Mother Nature to reveal the inner workings of the fruit fly's biological clock.
Dr. Takahashi describes the powerful strategies that he and others have harnessed for understanding biological clocks in mammals.
The heart acts as a dual pump, sending oxygen-depleted blood to the lungs to be reinvigorated and pumping oxygen-rich blood to vital organs throughout the body.
The discovery of DNA as the basis of heredity led to an explosive growth of knowledge about the human genome and allowed the identification of genes that predispose people to different diseases.
Although heart disease typically occurs after middle age, seemingly fit and healthy young individuals can die suddenly from unrecognized heart disease.
Molecular genetic approaches have identified genes that, when mutated, cause either increased or decreased blood pressure.
Cellular enzymes are catalysts that tame reactions by accelerating them, lending specificity, and regulating their time and place.
Discovery of RNA's catalytic activity led to unexpected spin-offs, including a new scenario for the origin of life.
Studies of RNA catalytic centers have revealed much about their structure and mode of action.
The chromosome ends, or telomeres, are necessary for DNA stability and replication.
Microbes have been the dominant life form throughout Earth's history. Eukaryotes and animals evolved only after microbes evolved oxygen-generating photosynthesis.
The theory of plate tectonics took many decades to become accepted. The process by which it was finally accepted provides a fascinating glimpse into how scientists build new scientific consensus.
Earth has been both cooler and warmer in the past, but the change is usually gradual. The current rate of carbon dioxide increase is unprecedented in human history, and solutions to mitigate its effect on global warming are challenging to implement.
Scientific evidence for global climate change is overwhelming, yet the American public remains skeptical. History provides insights into how a Cold War-era think tank became an influential source of anti-regulation sentiment.
A discussion on climate change with the students attending the 2012 Holiday Lectures on Science.
Students discuss the short film after a screening at the 2012 Holiday Lectures on Science.
The human body has at least a trillion ways of recognizing that something foreign has invaded.
The immune system recognizes invaders in a complex way.
Normally the trillions of lymphocytes in the human body do not attack their host.
Some organisms have evolved ways of evading or subverting the body's defenses.
Recent advances in DNA sequencing technology have led to a better understanding of the many genes that play a role in brain development.
Understanding that cancer is caused by mutations in genes that regulate cell proliferation has led to the development of targeted drug therapies.
Over the past decade, the application of advanced DNA sequencing techniques has greatly increased our understanding of the genetic basis of autism.
Genetic data from a large number of tumor types reveal commonly mutated genes and uncover connections between different types of cancer.
A student discussion with the lecturers of the 2013 Holiday Lectures on Science.
Dr. Elinor Karlsson discusses her work with dogs as a model organism for genomic studies.
There is still time to avoid a sixth mass extinction.
Human activities and their effects on biodiversity in the past, present, and future.
How to preserve genetic diversity that is threatened by habitat loss.
The threat to biodiversity in the ocean differs from the threats on the land.
Coral reefs, how they are threatened by climate change, and how to protect them.
What steps can be taken to avoid the sixth mass extinction?