Highlights d Adaptive light-sheet microscopy captures mouse development at the single-cell level d We analyzed embryo-wide cell dynamics from gastrulation to early organogenesis d We reconstructed high-resolution fate maps and maps of tissue morphogenesis d We created a statistical, dynamic atlas of development from multiple embryos

A technique for measuring broadband near-infrared absorption spectra of turbid media that uses a combination of frequency-domain ͑FD͒ and steady-state ͑SS͒ reflectance methods is presented. Most of the wavelength coverage is provided by a white-light SS measurement, whereas the FD data are acquired at a few selected wavelengths. Coefficients of absorption ͑ a ͒ and reduced scattering ͑Ј s ͒ derived from the FD data are used to calibrate the intensity of the SS measurements and to estimate Ј s at all wavelengths in the spectral window of interest. After these steps are performed, one can determine a by comparing the SS reflectance values with the predictions of diffusion theory, wavelength by wavelength. Absorption spectra of a turbid phantom and of human breast tissue in vivo, derived with the combined SSFD technique, agree well with expected reference values. All measurements can be performed at a single source-detector separation distance, reducing the variations in sampling volume that exist in multidistance methods. The technique uses relatively inexpensive light sources and detectors and is easily implemented on an existing multiwavelength FD system.