(CBS) - Science and forensic analysis have been center stage today at the Casey Anthony murder trial.
Chemist Michael Sigman, a former employee of the Oak Ridge National Laboratory and now a professor at the University of Central Florida, was the first scientist to take air samples from the trunk of Anthony's car.
Sigman told the jury he took a total of six samples, repeating the process because results from the initial samples were so weak and only detected the presence of gasoline. Sigman says further more sophisticated tests turned up additional chemical compounds which are often found in cabbage, onions bleach and spot removers. A prosecution witness had previously said those compounds are also present in human decompositon. Dr. Sigman disagreed, telling the jury, "I can't say that decomposition occurred in that car."
Prosecutors claim Anthony hid the body of her 2-year-old daughter Caylee in the trunk of her car.
Dr. Sigman has yet to undergo cross examination.
Earlier today, defense attorneys called a forensic geologist and forensic toxicologist, both employed by the FBI, to the stand. The geologist testified that no soil match was made between the site where Caylee's body was found and material found on Casey's shoes retrieved from her home. The toxicologist tested the child's hair for drugs that might have been used to put her to sleep. Madeline Montgomery said she found nothing.
This will be an abbreviated day in court. Judge Belvin Perry Jr. is adjourning the case at lunchtime so that he can attend a meeting. The jurors will likely welcome the respite from detailed scientific testimony. Observers within the courtroom say that jurors have been yawning and fidgeting for much of the morning.
Post contributed by Lisa Meyer-Steinhaus