Final answer:
Ichnofossils below the photic zone would likely include traces from organisms adapted to the aphotic conditions, characterized by horizontal burrows and other marks by non-photosynthetic organisms.
Step-by-step explanation:
Ichnofossils expected below the photic zone are typically indicative of the organisms that lived in the aphotic regions of the ocean. Since the photic zone extends to a maximum depth of 200 meters where photosynthesis can occur, below this level in the aphotic zone, you will not find photosynthetic organisms.
Instead, you would expect to find trace fossils created by detritivores and other organisms that feed on the matter sinking from the photic zone.
The ichnofacies found in deeper waters are usually characterized by horizontal burrows, reflecting the movement and activities of organisms in those environments. The types of ichnofossils might include burrows, feeding marks, or resting traces of organisms such as sea cucumbers found in the abyssal zone.
These trace fossils give us critical information about the paleoenvironment, including the absence of light, and hence the nonexistence of photosynthetic life forms.