Multiple movies and TV shows have depicted armies besieging a fortress and eventually resorting to a large battering ram to get through the front gates, either carried or swinging from some chains (Return of the King?) with a metal head of some animal attached to the front.
Did armies put any sort of "cap" on the front of battering rams to make them more effective? Were they even effective to begin with? Finally, if they *did* put some sort of hardened endpoints on the battering rams, did they ever shape them in the head of some animal? Why would they do this?
Battering rams are very effective and attested in artwork and writing from the ancient world. I talk a bit about ram's effectiveness and how it differs from the "videogame experience" here.
I was going to say that animal heads probably wasn't a thing. They are depicted in "historical" manuscripts from early modern periods which sometimes takes a more fanciful approach. The "hardened endpoint" was absolutely used. Most of the stuff depicted when I poured through some books are of pointed such heads. The Ancient Greeks well understood the concept of making a pointed head and even had a variation of the ram known as a "borer" as it was effectively a large stone drill. Such devises were used into the medieaval period too. Another example is a bronze wedge shaped ramhead (complete with a small embossed ram's head on the side, which suggests the idea of connecting a ram, the animal, with a ram the thing has been around) found at Olympia from the late 5th century (BC I think they mean). It is suggested it was designed to cut through brick type materials, common in the region for building various structures including citywalls. So metal headed rams were absolutely common and they shaped them to improve penetration.
Animal heads though? Apparently both Josephus ("Rome's Jewish Wars") AD 66-73 and Marcellanus writing in the AD 360s mention ram's heads cast in animal shapes, if I paraphrase them: shaped as a ram's head as is customary, which gives the ram it's name. The why question doesn't seem explicitly answerable. The shape of the head matters some depending on what kinda of material the walls is built from. I suspect the Roman's use, and they were more liable to escalade the walls, is partly because it made for a great pun. That they had a sense of humour can be seen in e.g. sling pellets cast in lead with messages on them, like "this hurts". But there is also likely what I can best describe as mystical approach to it. You want to bestow the "spirit" of the animal to the ram so it err rams better. I won't say there isn't a good explanation I just can't find anyone at this moment mentioned.
Ancient Siege Warfare, Persians, Greeks, Carthaginians and Romans 546-146 BC, Duncan Campbell (2005)
Greek and Roman Siege Machinery 399 BC- AD 363, Duncan Campbell (2003)
Medieval Siege Warfare, Christopher Gravett (1990)
Siege Warfare in the Roman World 146 BC-AD 378, Duncan Campbell (2005)